Archives of biochemistry and biophysics最新文献_第5页

Altered dimerization of certain riboflavin transporter 2 mutants: a possible source of UPR, altered calcium signalling and mitochondrial derangements in RTD2 某些核黄素转运蛋白2突变体的二聚化改变：RTD2中UPR、钙信号改变和线粒体紊乱的可能来源

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-22 DOI: 10.1016/j.abb.2025.110675

Maria Tolomeo , Valentina Magliocca , Stefania Petrini , Alessia Nisco , Roberto Barbaro , Martina Lanza , Michela Piccione , Anna Maria Giudetti , Keith Massey , Lara Console , Cesare Indiveri , Katia Zanier , Enrico Bertini , Tiziana Persichini , Claudia Compagnucci , Matilde Colella , Maria Barile

Riboflavin transporter deficiency Type 2 (RTD2, OMIM #614707), formerly known as Brown-Vialetto-Van Laere Syndrome 2 (BVVLS 2), is a rare autosomal recessive neurodegenerative disorder caused by biallelic variants in the SLC52A2 gene, encoding for riboflavin transporter 2 (RFVT2). This transporter plays a critical role in flavin cofactor delivery, particularly in the brain. Clinically, RTD2 presents with progressive hearing loss, optic atrophy, muscle weakness, respiratory issues, and pontobulbar palsy. Current treatment involves high-dose riboflavin and other supplements.

In this study we explored the molecular mechanisms behind RTD2, focusing on the dimerization of RFVT2 and the associated cellular stress mechanisms in patient-specific models. We demonstrated that RFVT2 exists as a homodimer and that pathogenic variants significantly impair its dimerization, which may contribute to the induction of ER stress. This hypothesis was supported by elevated levels of BiP, an ER stress marker, in patient iPSC-derived motor neurons. Similar findings were confirmed in patient-derived fibroblasts, where we also observed mitochondrial dysfunction and disrupted calcium signaling. Interestingly, no significant changes in FAD content were detected in both cell models, suggesting that proteotoxic stress may be a crucial pathogenic mechanism in RTD2, even in the absence of signs of FAD deficiency. FAD autofluorescence and FLIM measurements reinforce the occurrence of mitochondrial dysfunction in patient MNs.

These findings provide insight into the pathogenic mechanisms of RTD2, highlighting the critical role of RFVT2 misfolding, ER stress, and mitochondrial dysfunction in this neurodegenerative disorder.

核黄素转运蛋白缺乏症2型（RTD2, omim# 614707），以前称为Brown-Vialetto-Van Laere综合征2 (BVVLS 2)，是一种罕见的常染色体隐性遗传神经退行性疾病，由编码核黄素转运蛋白2 （RFVT2）的SLC52A2基因的双等位变异引起。这种转运体在黄素辅助因子的传递中起着至关重要的作用，特别是在大脑中。临床上，RTD2表现为进行性听力丧失、视神经萎缩、肌肉无力、呼吸问题和桥球麻痹。目前的治疗包括大剂量核黄素和其他补充剂。在这项研究中，我们探索了RTD2背后的分子机制，重点研究了RFVT2的二聚化和患者特异性模型中相关的细胞应激机制。我们证明了RFVT2作为一种同二聚体存在，并且致病变异显著损害了其二聚体，这可能有助于诱导内质网应激。这一假设得到了患者ipsc源性运动神经元中内质网应激标志物BiP水平升高的支持。在患者来源的成纤维细胞中也证实了类似的发现，我们也观察到线粒体功能障碍和钙信号中断。有趣的是，在两种细胞模型中均未检测到FAD含量的显著变化，这表明即使在没有FAD缺乏迹象的情况下，蛋白毒性应激可能是RTD2的关键致病机制。FAD自身荧光和FLIM测量加强了患者MNs线粒体功能障碍的发生。这些发现提供了对RTD2致病机制的深入了解，强调了RFVT2错误折叠、内质网应激和线粒体功能障碍在这种神经退行性疾病中的关键作用。

{"title":"Altered dimerization of certain riboflavin transporter 2 mutants: a possible source of UPR, altered calcium signalling and mitochondrial derangements in RTD2","authors":"Maria Tolomeo , Valentina Magliocca , Stefania Petrini , Alessia Nisco , Roberto Barbaro , Martina Lanza , Michela Piccione , Anna Maria Giudetti , Keith Massey , Lara Console , Cesare Indiveri , Katia Zanier , Enrico Bertini , Tiziana Persichini , Claudia Compagnucci , Matilde Colella , Maria Barile","doi":"10.1016/j.abb.2025.110675","DOIUrl":"10.1016/j.abb.2025.110675","url":null,"abstract":"<div><div>Riboflavin transporter deficiency Type 2 (RTD2, OMIM #614707), formerly known as Brown-Vialetto-Van Laere Syndrome 2 (BVVLS 2), is a rare autosomal recessive neurodegenerative disorder caused by biallelic variants in the <em>SLC52A2</em> gene, encoding for riboflavin transporter 2 (RFVT2). This transporter plays a critical role in flavin cofactor delivery, particularly in the brain. Clinically, RTD2 presents with progressive hearing loss, optic atrophy, muscle weakness, respiratory issues, and pontobulbar palsy. Current treatment involves high-dose riboflavin and other supplements.</div><div>In this study we explored the molecular mechanisms behind RTD2, focusing on the dimerization of RFVT2 and the associated cellular stress mechanisms in patient-specific models. We demonstrated that RFVT2 exists as a homodimer and that pathogenic variants significantly impair its dimerization, which may contribute to the induction of ER stress. This hypothesis was supported by elevated levels of BiP, an ER stress marker, in patient iPSC-derived motor neurons. Similar findings were confirmed in patient-derived fibroblasts, where we also observed mitochondrial dysfunction and disrupted calcium signaling. Interestingly, no significant changes in FAD content were detected in both cell models, suggesting that proteotoxic stress may be a crucial pathogenic mechanism in RTD2, even in the absence of signs of FAD deficiency. FAD autofluorescence and FLIM measurements reinforce the occurrence of mitochondrial dysfunction in patient MNs.</div><div>These findings provide insight into the pathogenic mechanisms of RTD2, highlighting the critical role of RFVT2 misfolding, ER stress, and mitochondrial dysfunction in this neurodegenerative disorder.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110675"},"PeriodicalIF":3.0,"publicationDate":"2025-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145595780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

γM23K mutation enhances ADP inhibition of mitochondrial F-ATPase yet has a minor effect on yeast growth rate γM23K突变增强ADP对线粒体f - atp酶的抑制作用，但对酵母生长速率影响较小。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-21 DOI: 10.1016/j.abb.2025.110674

Valeria M. Zubareva , Kseniia V. Galkina , Anna S. Lapashina , Svyatoslav S. Sokolov , Olga V. Markova , Dmitry A. Knorre , Boris A. Feniouk

ADP inhibition of ATP hydrolysis is a conserved regulatory mechanism found in virtually all F-type ATP synthases. It occurs when ADP binds tightly to a catalytic site in the absence of phosphate, locking the enzyme in an inactive conformation. This inhibition is thought to prevent wasteful ATP hydrolysis, particularly under conditions where the proton-motive force is insufficient to drive ATP synthesis. However, the physiological significance of this mechanism remains unclear.

To explore this further, we introduced the γM23K mutation—previously shown to enhance ADP inhibition in bacterial ATP synthases—into the yeast mitochondrial ATP synthase by engineering the corresponding ATP3M23K substitution in Saccharomyces cerevisiae.

In isolated mitochondria, this mutation did not impair ATP synthesis but significantly increased the sensitivity of ATPase activity to ADP and azide, indicating enhanced ADP inhibition. In vivo, the mutation had no effect on growth under fermentable conditions and only mildly reduced the growth rate of rho⁺ cells on a non-fermentable carbon source. Contrary to expectations, the ATP3M23K mutation did not impair the growth rate or viability of rho⁰ cells, which rely on ATP hydrolysis in the matrix to maintain mitochondrial membrane potential via ATP/ADP exchange with the cytoplasm. Furthermore, no significant differences were observed in lag phase duration following prolonged starvation, nor in ATP content in stationary-phase cultures. These findings confirm that ADP inhibition can be selectively enhanced in yeast F_OF₁-ATPase without disrupting ATP synthesis, but also suggest that this regulatory mechanism plays a limited role in shaping cellular physiology under standard laboratory conditions.

ADP对ATP水解的抑制是一种保守的调节机制，几乎在所有f型ATP合酶中都存在。当ADP在没有磷酸盐的情况下与催化位点紧密结合，将酶锁定在非活性构象中时，就会发生这种情况。这种抑制作用被认为可以防止浪费的ATP水解，特别是在质子动力不足以驱动ATP合成的情况下。然而，这一机制的生理意义尚不清楚。为了进一步探索这一点，我们通过在酿酒酵母中设计相应的ATP3M23K取代，将γM23K突变引入酵母线粒体ATP合酶中，该突变先前被证明可以增强细菌ATP合酶中ADP的抑制作用。在分离的线粒体中，该突变不影响ATP合成，但显著增加了ATP酶活性对ADP和叠氮化物的敏感性，表明ADP抑制作用增强。在体内，该突变对可发酵条件下的生长没有影响，仅轻度降低了rho+细胞在不可发酵碳源上的生长速度。与预期相反，ATP3M23K突变并未损害rho0细胞的生长速度或活力，rho0细胞依靠基质中的ATP水解通过与细胞质交换ATP/ADP来维持线粒体膜电位。此外，在长时间饥饿后的滞后期持续时间和静止期培养中ATP含量没有显著差异。这些发现证实，在不破坏ATP合成的情况下，酵母fof1 -ATP酶可以选择性地增强ADP的抑制作用，但也表明，在标准实验室条件下，这种调节机制在塑造细胞生理方面的作用有限。

{"title":"γM23K mutation enhances ADP inhibition of mitochondrial F-ATPase yet has a minor effect on yeast growth rate","authors":"Valeria M. Zubareva , Kseniia V. Galkina , Anna S. Lapashina , Svyatoslav S. Sokolov , Olga V. Markova , Dmitry A. Knorre , Boris A. Feniouk","doi":"10.1016/j.abb.2025.110674","DOIUrl":"10.1016/j.abb.2025.110674","url":null,"abstract":"<div><div>ADP inhibition of ATP hydrolysis is a conserved regulatory mechanism found in virtually all F-type ATP synthases. It occurs when ADP binds tightly to a catalytic site in the absence of phosphate, locking the enzyme in an inactive conformation. This inhibition is thought to prevent wasteful ATP hydrolysis, particularly under conditions where the proton-motive force is insufficient to drive ATP synthesis. However, the physiological significance of this mechanism remains unclear.</div><div>To explore this further, we introduced the γM23K mutation—previously shown to enhance ADP inhibition in bacterial ATP synthases—into the yeast mitochondrial ATP synthase by engineering the corresponding ATP3M23K substitution in <em>Saccharomyces cerevisiae</em>.</div><div>In isolated mitochondria, this mutation did not impair ATP synthesis but significantly increased the sensitivity of ATPase activity to ADP and azide, indicating enhanced ADP inhibition. <em>In vivo</em>, the mutation had no effect on growth under fermentable conditions and only mildly reduced the growth rate of <em>rho</em><sup><em>+</em></sup> cells on a non-fermentable carbon source. Contrary to expectations, the ATP3M23K mutation did not impair the growth rate or viability of <em>rho</em><sup><em>0</em></sup> cells, which rely on ATP hydrolysis in the matrix to maintain mitochondrial membrane potential via ATP/ADP exchange with the cytoplasm. Furthermore, no significant differences were observed in lag phase duration following prolonged starvation, nor in ATP content in stationary-phase cultures. These findings confirm that ADP inhibition can be selectively enhanced in yeast F<sub>O</sub>F<sub>1</sub>-ATPase without disrupting ATP synthesis, but also suggest that this regulatory mechanism plays a limited role in shaping cellular physiology under standard laboratory conditions.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110674"},"PeriodicalIF":3.0,"publicationDate":"2025-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145585884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

MiR-133a encapsulated in hyaluronic acid nanoparticles alleviates sepsis-induced cardiomyopathy by decreasing M1 macrophage polarization via the SOCS3/JAK/STAT3 pathway 透明质酸纳米颗粒包裹的MiR-133a通过SOCS3/JAK/STAT3通路降低M1巨噬细胞极化，从而减轻败血症诱导的心肌病。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-17 DOI: 10.1016/j.abb.2025.110673

Changrui Zheng , Yuqiang Gao , Xuehan Wei , Xiaohong Huang , Dayan Wu , Jia Tian

Background

Sepsis-induced cardiomyopathy (SIC) is a reversible myocardial dysfunction driven by excessive inflammation, with M1 macrophage polarization as a major contributor. This study explored the regulatory role of the miR-133a/SOCS3 axis in macrophage polarization and myocardial injury and assessed a hyaluronic acid (HA)–based nanogel for targeted miR-133a delivery.

Methods

RAW264.7 macrophages were stimulated with LPS and co-cultured with H9C2 cardiomyocytes, followed by transfection with miR-133a mimics/inhibitor or SOCS3 overexpression plasmids. The direct binding between miR-133a and SOCS3 was verified by dual-luciferase reporter assay. A cecal ligation and puncture (CLP) rat model was used to assess in vivo therapeutic effects after intravenous administration of free or HA-encapsulated miR-133a. Macrophage polarization was measured by flow cytometry and qRT-PCR; inflammatory cytokines by ELISA; protein expression (SOCS3, JAK/STAT3 pathway, iNOS, CD206) by Western blot and immunohistochemistry; apoptosis by TUNEL; and myocardial injury by H&E staining.

Results

MiR-133a was significantly downregulated in LPS-treated macrophages and in SIC blood samples, with levels inversely correlated to SOCS3. MiR-133a overexpression suppressed M1 polarization, cytokine production, and SOCS3 expression, while enhancing M2 polarization; these effects were reversed by SOCS3 overexpression. In co-culture, miR-133a reduced cardiomyocyte inflammation and apoptosis through SOCS3/JAK/STAT3 inhibition. In CLP rats, HA–miR-133a achieved greater myocardial accumulation than free mimics, attenuated histopathological damage, lowered cytokine levels, iNOS, and phosphorylated JAK3/STAT3, and increased CD206 expression.

Conclusion

MiR-133a alleviates SIC by inhibiting SOCS3/JAK/STAT3 signaling and promoting M2 polarization. HA-based targeted delivery enhances stability, tissue uptake, and therapeutic efficacy, representing a promising SIC therapy.

背景：败血症性心肌病（SIC）是一种由过度炎症驱动的可逆性心肌功能障碍，M1巨噬细胞极化是主要因素。本研究探讨了miR-133a/SOCS3轴在巨噬细胞极化和心肌损伤中的调节作用，并评估了基于透明质酸（HA）的纳米凝胶靶向miR-133a递送。方法：用LPS刺激RAW264.7巨噬细胞，与H9C2心肌细胞共培养，然后转染miR-133a模拟物/抑制剂或SOCS3过表达质粒。通过双荧光素酶报告基因实验验证了miR-133a与SOCS3的直接结合。采用盲肠结扎穿刺（CLP）大鼠模型来评估静脉注射游离或ha包封miR-133a后的体内治疗效果。采用流式细胞术和qRT-PCR检测巨噬细胞极化；ELISA检测炎性因子；蛋白表达（SOCS3、JAK/STAT3通路、iNOS、CD206）；TUNEL诱导细胞凋亡；H&E染色心肌损伤。结果：MiR-133a在lps处理的巨噬细胞和SIC血液样本中显著下调，其水平与SOCS3呈负相关。MiR-133a过表达抑制M1极化、细胞因子产生和SOCS3表达，同时增强M2极化；这些影响被SOCS3过表达逆转。在共培养中，miR-133a通过抑制SOCS3/JAK/STAT3减少心肌细胞炎症和凋亡。在CLP大鼠中，HA-miR-133a比游离模拟物实现了更大的心肌积累，减轻了组织病理学损伤，降低了细胞因子水平、iNOS和磷酸化的JAK3/STAT3，并增加了CD206的表达。结论：MiR-133a通过抑制SOCS3/JAK/STAT3信号通路和促进M2极化来缓解SIC。基于ha的靶向给药增强了稳定性、组织吸收和治疗效果，是一种很有前途的SIC治疗方法。

{"title":"MiR-133a encapsulated in hyaluronic acid nanoparticles alleviates sepsis-induced cardiomyopathy by decreasing M1 macrophage polarization via the SOCS3/JAK/STAT3 pathway","authors":"Changrui Zheng , Yuqiang Gao , Xuehan Wei , Xiaohong Huang , Dayan Wu , Jia Tian","doi":"10.1016/j.abb.2025.110673","DOIUrl":"10.1016/j.abb.2025.110673","url":null,"abstract":"<div><h3>Background</h3><div>Sepsis-induced cardiomyopathy (SIC) is a reversible myocardial dysfunction driven by excessive inflammation, with M1 macrophage polarization as a major contributor. This study explored the regulatory role of the miR-133a/SOCS3 axis in macrophage polarization and myocardial injury and assessed a hyaluronic acid (HA)–based nanogel for targeted miR-133a delivery.</div></div><div><h3>Methods</h3><div>RAW264.7 macrophages were stimulated with LPS and co-cultured with H9C2 cardiomyocytes, followed by transfection with miR-133a mimics/inhibitor or SOCS3 overexpression plasmids. The direct binding between miR-133a and SOCS3 was verified by dual-luciferase reporter assay. A cecal ligation and puncture (CLP) rat model was used to assess <em>in vivo</em> therapeutic effects after intravenous administration of free or HA-encapsulated miR-133a. Macrophage polarization was measured by flow cytometry and qRT-PCR; inflammatory cytokines by ELISA; protein expression (SOCS3, JAK/STAT3 pathway, iNOS, CD206) by Western blot and immunohistochemistry; apoptosis by TUNEL; and myocardial injury by H&E staining.</div></div><div><h3>Results</h3><div>MiR-133a was significantly downregulated in LPS-treated macrophages and in SIC blood samples, with levels inversely correlated to SOCS3. MiR-133a overexpression suppressed M1 polarization, cytokine production, and SOCS3 expression, while enhancing M2 polarization; these effects were reversed by SOCS3 overexpression. In co-culture, miR-133a reduced cardiomyocyte inflammation and apoptosis through SOCS3/JAK/STAT3 inhibition. In CLP rats, HA–miR-133a achieved greater myocardial accumulation than free mimics, attenuated histopathological damage, lowered cytokine levels, iNOS, and phosphorylated JAK3/STAT3, and increased CD206 expression.</div></div><div><h3>Conclusion</h3><div>MiR-133a alleviates SIC by inhibiting SOCS3/JAK/STAT3 signaling and promoting M2 polarization. HA-based targeted delivery enhances stability, tissue uptake, and therapeutic efficacy, representing a promising SIC therapy.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110673"},"PeriodicalIF":3.0,"publicationDate":"2025-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145556104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Photorin controls the intracellular activation and bacteriotoxic effect of Photorhabdus laumondii protease S during its expression in Escherichia coli Photorin在大肠杆菌中表达过程中控制laumondii光habdus蛋白酶S的胞内活化和细菌毒性作用

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-13 DOI: 10.1016/j.abb.2025.110672

Anastasia O. Svetlova , Alexey A. Komissarov , Maria A. Karaseva , Ksenia N. Chukhontseva , Olga V. Pobeguts , Mariya A. Galyamina , Igor P. Smirnov , Polina D. Kuchur , Anna O. Izotova , Stepan V. Toshchakov , Ilya V. Demidyuk

An important role in the regulation of protease activity in living systems is played by their propeptides and endogenous protein inhibitors. Both are capable of repressing enzyme activity, ensuring it occurs only at the right time and/or in the right place. Therefore, propeptides and inhibitors may appear to perform the same function. However, many proteases have both, but the interplay between these two modes of regulation remains virtually unexplored. We investigated the role of the propeptide of Photorhabdus laumondii protealysin-like protease S (PrtS) and its emfourin-like inhibitor (ELI), photorin, in controlling intracellular enzyme activation in an Escherichia coli model. In the absence of the inhibitor, PrtS was found to be activated within cells due to autocatalytic cleavage of the propeptide, which led to the death of most bacteria. Along with this, a bacterial population emerges in which PrtS gene transcription is suppressed apparently due to the action of epigenetic mechanisms. Thus, the propeptide alone is unable to suppress aberrant intracellular activity of PrtS, whereas photorin protects cells from the toxic effect of PrtS and prevents inactivation of its gene. In summary, using PrtS as an example, we demonstrated for the first time that protealysin-like proteases (PLPs) which are ubiquitous in bacteria and are probably involved in pathogenesis, are toxic to bacteria. In this context, the function of ELIs, whose genes in bacterial genomes are co-localized with those of PLPs, is to protect bacteria from aberrant intracellular activity of PLPs.

蛋白酶的前肽和内源性蛋白抑制剂在生物系统中发挥着重要的调节作用。两者都能够抑制酶的活性，确保它只在正确的时间和/或在正确的地方发生。因此，前肽和抑制剂似乎具有相同的功能。然而，许多蛋白酶两者都有，但这两种调节模式之间的相互作用实际上尚未被探索。在大肠杆菌模型中，研究了laumondii光habdus protealysin样蛋白酶S （PrtS）前肽及其emfourin样抑制剂（ELI） photorin在控制胞内酶激活中的作用。在缺乏抑制剂的情况下，由于前肽的自催化裂解，PrtS被发现在细胞内被激活，导致大多数细菌死亡。与此同时，出现了一种由于表观遗传机制的作用而明显抑制PrtS基因转录的细菌群体。因此，单独的前肽无法抑制PrtS的细胞内异常活性，而光素可以保护细胞免受PrtS的毒性作用，并防止其基因失活。总之，以PrtS为例，我们首次证明了在细菌中普遍存在并可能参与致病机制的蛋白溶素样蛋白酶（PLPs）对细菌具有毒性。在这种情况下，细菌基因组中的ELIs基因与PLPs基因共定位，其功能是保护细菌免受PLPs细胞内异常活性的影响。

{"title":"Photorin controls the intracellular activation and bacteriotoxic effect of Photorhabdus laumondii protease S during its expression in Escherichia coli","authors":"Anastasia O. Svetlova , Alexey A. Komissarov , Maria A. Karaseva , Ksenia N. Chukhontseva , Olga V. Pobeguts , Mariya A. Galyamina , Igor P. Smirnov , Polina D. Kuchur , Anna O. Izotova , Stepan V. Toshchakov , Ilya V. Demidyuk","doi":"10.1016/j.abb.2025.110672","DOIUrl":"10.1016/j.abb.2025.110672","url":null,"abstract":"<div><div>An important role in the regulation of protease activity in living systems is played by their propeptides and endogenous protein inhibitors. Both are capable of repressing enzyme activity, ensuring it occurs only at the right time and/or in the right place. Therefore, propeptides and inhibitors may appear to perform the same function. However, many proteases have both, but the interplay between these two modes of regulation remains virtually unexplored. We investigated the role of the propeptide of <em>Photorhabdus laumondii</em> protealysin-like protease S (PrtS) and its emfourin-like inhibitor (ELI), photorin, in controlling intracellular enzyme activation in an <em>Escherichia coli</em> model. In the absence of the inhibitor, PrtS was found to be activated within cells due to autocatalytic cleavage of the propeptide, which led to the death of most bacteria. Along with this, a bacterial population emerges in which PrtS gene transcription is suppressed apparently due to the action of epigenetic mechanisms. Thus, the propeptide alone is unable to suppress aberrant intracellular activity of PrtS, whereas photorin protects cells from the toxic effect of PrtS and prevents inactivation of its gene. In summary, using PrtS as an example, we demonstrated for the first time that protealysin-like proteases (PLPs) which are ubiquitous in bacteria and are probably involved in pathogenesis, are toxic to bacteria. In this context, the function of ELIs, whose genes in bacterial genomes are co-localized with those of PLPs, is to protect bacteria from aberrant intracellular activity of PLPs.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110672"},"PeriodicalIF":3.0,"publicationDate":"2025-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145526749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hirudin promotes peripheral nerve repair and alleviates pain by regulating the EGFR-PI3K/AKT/mTOR pathway 水蛭素通过调节EGFR-PI3K/AKT/mTOR通路促进周围神经修复，减轻疼痛。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-10 DOI: 10.1016/j.abb.2025.110671

Long Wu , Zhe Zhang , Dongbo Tian , Kaiye Chen , Jing-hao Liang , Heng Yu , Ke Wang , Kongbin Chen , Yifan Wu , Hede Yan

Purpose

Peripheral nerve injury (PNI) often results in severe neuropathic pain and impaired nerve regeneration. Hirudin, derived from the traditional Chinese medicinal leech, has not yet been investigated for its therapeutic potential in the treatment of PNI.

Methods

A total of 144 male Sprague-Dawley rats were subjected to a sciatic nerve crush injury model. Rats were grouped into 5 cohorts: sham, control, PNI + Hirudin (10 mg/kg), PNI + Hirudin (15 mg/kg), and PNI + Hirudin (15 mg/kg) + NSC228155. There were various assessments conducted, including histological staining, immunofluorescence, transmission electron microscopy (TEM), behavioral tests, and Western blot analyses.

Results

Our experiments demonstrated that Hirudin significantly improved the structural integrity of regenerating nerves, enhanced orderly axonal regeneration and remyelination. It also alleviated neuropathic pain, as evidenced by reduced autotomy scores and decreased expression of pain-related markers (Iba-1, C-Fos, and substance P). Mechanistic studies revealed that Hirudin downregulated the activation of the EGFR-dependent PI3K/AKT/mTOR signaling pathway, which contributed to its therapeutic effects.

Conclusion

Hirudin can effectively enhance peripheral nerve regeneration and alleviate neuropathic pain following PNI. These findings suggest that Hirudin holds promise as a therapeutic agent for the treatment of PNI-induced neuropathic pain and impaired nerve regeneration.

目的：周围神经损伤（PNI）常导致严重的神经性疼痛和神经再生受损。水蛭素来源于中药水蛭，目前尚未对其治疗PNI的潜力进行研究。方法：采用144只雄性sd大鼠建立坐骨神经挤压损伤模型。将大鼠分为5组：假手术组、对照组、PNI +水蛭素（10 mg/kg）、PNI +水蛭素（15 mg/kg）、PNI +水蛭素(15 mg/kg) + NSC228155。进行了各种评估，包括组织学染色，免疫荧光，透射电子显微镜（TEM），行为测试和western blot分析。结果：水蛭素能明显改善再生神经的结构完整性，促进轴突有序再生和髓鞘再生。自体切开术评分降低，疼痛相关标记物（Iba-1、C-Fos和P物质）表达降低，也可以缓解神经性疼痛。机制研究显示水蛭素下调egfr依赖性PI3K/AKT/mTOR信号通路的激活，这有助于其治疗效果。结论：水蛭素能有效促进周围神经再生，减轻PNI术后神经性疼痛。这些发现表明水蛭素有望作为治疗pni诱导的神经性疼痛和神经再生受损的治疗剂。

{"title":"Hirudin promotes peripheral nerve repair and alleviates pain by regulating the EGFR-PI3K/AKT/mTOR pathway","authors":"Long Wu , Zhe Zhang , Dongbo Tian , Kaiye Chen , Jing-hao Liang , Heng Yu , Ke Wang , Kongbin Chen , Yifan Wu , Hede Yan","doi":"10.1016/j.abb.2025.110671","DOIUrl":"10.1016/j.abb.2025.110671","url":null,"abstract":"<div><h3>Purpose</h3><div>Peripheral nerve injury (PNI) often results in severe neuropathic pain and impaired nerve regeneration. Hirudin, derived from the traditional Chinese medicinal leech, has not yet been investigated for its therapeutic potential in the treatment of PNI.</div></div><div><h3>Methods</h3><div>A total of 144 male Sprague-Dawley rats were subjected to a sciatic nerve crush injury model. Rats were grouped into 5 cohorts: sham, control, PNI + Hirudin (10 mg/kg), PNI + Hirudin (15 mg/kg), and PNI + Hirudin (15 mg/kg) + NSC228155. There were various assessments conducted, including histological staining, immunofluorescence, transmission electron microscopy (TEM), behavioral tests, and Western blot analyses.</div></div><div><h3>Results</h3><div>Our experiments demonstrated that Hirudin significantly improved the structural integrity of regenerating nerves, enhanced orderly axonal regeneration and remyelination. It also alleviated neuropathic pain, as evidenced by reduced autotomy scores and decreased expression of pain-related markers (Iba-1, C-Fos, and substance P). Mechanistic studies revealed that Hirudin downregulated the activation of the EGFR-dependent PI3K/AKT/mTOR signaling pathway, which contributed to its therapeutic effects.</div></div><div><h3>Conclusion</h3><div>Hirudin can effectively enhance peripheral nerve regeneration and alleviate neuropathic pain following PNI. These findings suggest that Hirudin holds promise as a therapeutic agent for the treatment of PNI-induced neuropathic pain and impaired nerve regeneration.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110671"},"PeriodicalIF":3.0,"publicationDate":"2025-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145501538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aerobic exercise intervention improves angiotensin Ⅱ-induced cardiac remodeling by inhibiting RBP4-STRA6-Wnt/β-catenin pathway 有氧运动干预通过抑制RBP4-STRA6-Wnt/β-catenin通路改善血管紧张素Ⅱ诱导的心脏重构。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-06 DOI: 10.1016/j.abb.2025.110670

Jiayu Yao , Jinyun Wang , Shuo Lin , Guangyuan Sha , Shen Wang , Mengyun Yang , Zaoshang Chang , Jingbo Xia , Min Hu

Most cardiovascular diseases are accompanied by cardiac remodeling, but physical exercise can mitigate and decelerate this process. Retinol-binding protein 4 (RBP4) has been associated with cardiovascular disease in both basic research and clinical settings. Therefore, the present study aimed to investigate the mechanism underlying RBP4 in exercise ameliorating cardiac remodeling. Our findings indicate that mice model of angiotensin Ⅱ (Ang Ⅱ)-induced cardiac hypertrophy exhibited elevated blood pressure, impaired cardiac function, increased myocardial fibrosis, and mitochondrial degradation, alongside elevated RBP4 levels in myocardial tissue. A 9-week aerobic exercise regimen improved these indexes and decreased RBP4 expression. The cell surface receptor stimulated by retinoic acid 6 (STRA6), which serves as a membrane receptor for RBP4, is implicated in the activation of the Wnt/β-catenin signaling pathway, with its knockdown potentially inhibiting this pathway. Our subsequent analyses identified a significant upregulation of the STRA6 protein in myocardial tissue of the mice model of cardiac hypertrophy. Further investigations showed that total β-catenin levels remained unchanged, there was an increase in nuclear β-catenin, which enhanced the expression of matrix metalloproteinase 7 (MMP7) and cyclooxygenase 2 (COX2). These alterations were reversed following exercise intervention. The results suggest that RBP4 enhances STRA6 expression in cardiac hypertrophy mice hearts and facilitates β-catenin nuclear translocation and transcriptional activity, leading to elevated levels of MMP7 and COX2 expression. Aerobic exercise appears to attenuate the myocardial inflammatory response by reducing RBP4 expression and inhibiting the Wnt/β-catenin pathway, thereby ameliorating Ang Ⅱ-induced cardiac remodeling.

大多数心血管疾病都伴有心脏重构，但体育锻炼可以减轻和减缓这一过程。视黄醇结合蛋白4 （RBP4）在基础研究和临床环境中都与心血管疾病有关。因此，本研究旨在探讨RBP4在运动改善心脏重构中的作用机制。我们的研究结果表明，血管紧张素Ⅱ（AngⅡ）诱导的心脏肥厚小鼠模型表现出血压升高、心功能受损、心肌纤维化增加和线粒体降解，同时心肌组织中RBP4水平升高。为期9周的有氧运动方案改善了这些指标并降低了RBP4的表达。视黄酸6 （STRA6）刺激的细胞表面受体，作为RBP4的膜受体，与Wnt/β-catenin信号通路的激活有关，其敲低可能抑制该通路。我们随后的分析发现，心肌肥厚模型小鼠心肌组织中STRA6蛋白显著上调。进一步研究发现，β-catenin总水平不变，细胞核β-catenin增加，从而增强了基质金属蛋白酶7 （MMP7）和环氧合酶2 （COX2）的表达。这些改变在运动干预后被逆转。结果表明，RBP4增强STRA6在心肌肥厚小鼠心脏中的表达，促进β-catenin核易位和转录活性，导致MMP7和COX2表达水平升高。有氧运动似乎通过降低RBP4表达和抑制Wnt/β-catenin通路来减轻心肌炎症反应，从而改善AngⅡ诱导的心脏重构。

{"title":"Aerobic exercise intervention improves angiotensin Ⅱ-induced cardiac remodeling by inhibiting RBP4-STRA6-Wnt/β-catenin pathway","authors":"Jiayu Yao , Jinyun Wang , Shuo Lin , Guangyuan Sha , Shen Wang , Mengyun Yang , Zaoshang Chang , Jingbo Xia , Min Hu","doi":"10.1016/j.abb.2025.110670","DOIUrl":"10.1016/j.abb.2025.110670","url":null,"abstract":"<div><div>Most cardiovascular diseases are accompanied by cardiac remodeling, but physical exercise can mitigate and decelerate this process. Retinol-binding protein 4 (RBP4) has been associated with cardiovascular disease in both basic research and clinical settings. Therefore, the present study aimed to investigate the mechanism underlying RBP4 in exercise ameliorating cardiac remodeling. Our findings indicate that mice model of angiotensin Ⅱ (Ang Ⅱ)-induced cardiac hypertrophy exhibited elevated blood pressure, impaired cardiac function, increased myocardial fibrosis, and mitochondrial degradation, alongside elevated RBP4 levels in myocardial tissue. A 9-week aerobic exercise regimen improved these indexes and decreased RBP4 expression. The cell surface receptor stimulated by retinoic acid 6 (STRA6), which serves as a membrane receptor for RBP4, is implicated in the activation of the Wnt/β-catenin signaling pathway, with its knockdown potentially inhibiting this pathway. Our subsequent analyses identified a significant upregulation of the STRA6 protein in myocardial tissue of the mice model of cardiac hypertrophy. Further investigations showed that total β-catenin levels remained unchanged, there was an increase in nuclear β-catenin, which enhanced the expression of matrix metalloproteinase 7 (MMP7) and cyclooxygenase 2 (COX2). These alterations were reversed following exercise intervention. The results suggest that RBP4 enhances STRA6 expression in cardiac hypertrophy mice hearts and facilitates β-catenin nuclear translocation and transcriptional activity, leading to elevated levels of MMP7 and COX2 expression. Aerobic exercise appears to attenuate the myocardial inflammatory response by reducing RBP4 expression and inhibiting the Wnt/β-catenin pathway, thereby ameliorating Ang Ⅱ-induced cardiac remodeling.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110670"},"PeriodicalIF":3.0,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145476575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

BACH1 drives ferroptosis in lung ischemia-reperfusion injury through epigenetic suppression of STAT3-Mediated antioxidant defense 通过表观遗传抑制stat3介导的抗氧化防御，BACH1驱动肺缺血再灌注损伤中的铁凋亡。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-03 DOI: 10.1016/j.abb.2025.110669

Ying Gu , Xiuli Liu , Xiaojun Zhang , Ning Zhang

Background

Lung ischemia-reperfusion injury (LIRI) is a major complication in lung transplantation, with ferroptosis as a key mechanism. The role of BACH1, a regulator of oxidative stress and iron metabolism, in LIRI-associated ferroptosis is unclear. This study explores whether BACH1 promotes LIRI via ferroptosis-related pathways.

Methods

The GSE9634 dataset was analyzed to identify BACH1-regulated networks in LIRI. MLE-12 alveolar epithelial cells underwent hypoxia-reoxygenation with BACH1 overexpression or knockdown, with or without PU.1/SHP1 inhibitors. Protein expression was evaluated by Western blot and immunofluorescence, and oxidative stress markers (MDA, ROS) and antioxidant enzyme activity (SOD) by ELISA. A rat LIRI model with lentiviral BACH1 modulation was used for in vivo validation, assessed via histopathology, TUNEL staining, and immunohistochemistry.

Results

BACH1 positively correlated with KDM4C and PU.1 but negatively with STAT3. BACH1 overexpression upregulated KDM4C, reduced H3K9me3 methylation, and activated PU.1, promoting SHP1-mediated STAT3 dephosphorylation. This suppressed antioxidant proteins (GPX4, SLC7A11, FTH1), increasing ferroptosis. PU.1/SHP1 inhibition restored STAT3 phosphorylation and antioxidant expression, reducing oxidative damage. In vivo, BACH1 overexpression worsened lung injury and apoptosis, while knockdown was protective. Immunohistochemistry showed BACH1 upregulation reduced phospho-STAT3 and SLC7A11 in injured tissue.

Conclusion

BACH1 drives ferroptosis-mediated LIRI via a KDM4C/PU.1/SHP1 axis, suppressing the STAT3/GPX4/SLC7A11/FTH1 pathway. Targeting BACH1 or its effectors offers therapeutic potential for LIRI prevention.

背景：肺缺血再灌注损伤（LIRI）是肺移植的主要并发症，铁下垂是其重要机制。作为氧化应激和铁代谢的调节因子，BACH1在lii相关铁下垂中的作用尚不清楚。本研究探讨BACH1是否通过凋亡相关途径促进LIRI。方法：分析GSE9634数据集，确定bach1调控的LIRI网络。使用或不使用PU.1/SHP1抑制剂时，MLE-12肺泡上皮细胞缺氧再氧化，BACH1过表达或敲低。Western blot和免疫荧光法检测蛋白表达，ELISA法检测氧化应激标志物（MDA、ROS）和抗氧化酶活性（SOD）。采用慢病毒BACH1调节的大鼠LIRI模型进行体内验证，通过组织病理学、TUNEL染色和免疫组织化学进行评估。结果：BACH1与KDM4C、PU.1呈正相关，与STAT3负相关。BACH1过表达上调KDM4C，降低H3K9me3甲基化，激活PU.1，促进shp1介导的STAT3去磷酸化。这抑制了抗氧化蛋白（GPX4, SLC7A11, FTH1），增加了铁下垂。PU.1/SHP1抑制恢复STAT3磷酸化和抗氧化表达，减轻氧化损伤。在体内，BACH1过表达加重了肺损伤和细胞凋亡，而低表达则具有保护作用。免疫组化显示BACH1上调可降低损伤组织中磷酸化stat3和SLC7A11。结论：BACH1通过KDM4C/PU驱动铁凋亡介导的LIRI。抑制STAT3/GPX4/SLC7A11/FTH1通路。靶向BACH1或其效应物为预防LIRI提供了治疗潜力。

{"title":"BACH1 drives ferroptosis in lung ischemia-reperfusion injury through epigenetic suppression of STAT3-Mediated antioxidant defense","authors":"Ying Gu , Xiuli Liu , Xiaojun Zhang , Ning Zhang","doi":"10.1016/j.abb.2025.110669","DOIUrl":"10.1016/j.abb.2025.110669","url":null,"abstract":"<div><h3>Background</h3><div>Lung ischemia-reperfusion injury (LIRI) is a major complication in lung transplantation, with ferroptosis as a key mechanism. The role of BACH1, a regulator of oxidative stress and iron metabolism, in LIRI-associated ferroptosis is unclear. This study explores whether BACH1 promotes LIRI via ferroptosis-related pathways.</div></div><div><h3>Methods</h3><div>The GSE9634 dataset was analyzed to identify BACH1-regulated networks in LIRI. MLE-12 alveolar epithelial cells underwent hypoxia-reoxygenation with BACH1 overexpression or knockdown, with or without PU.1/SHP1 inhibitors. Protein expression was evaluated by Western blot and immunofluorescence, and oxidative stress markers (MDA, ROS) and antioxidant enzyme activity (SOD) by ELISA. A rat LIRI model with lentiviral BACH1 modulation was used for in vivo validation, assessed via histopathology, TUNEL staining, and immunohistochemistry.</div></div><div><h3>Results</h3><div>BACH1 positively correlated with KDM4C and PU.1 but negatively with STAT3. BACH1 overexpression upregulated KDM4C, reduced H3K9me3 methylation, and activated PU.1, promoting SHP1-mediated STAT3 dephosphorylation. This suppressed antioxidant proteins (GPX4, SLC7A11, FTH1), increasing ferroptosis. PU.1/SHP1 inhibition restored STAT3 phosphorylation and antioxidant expression, reducing oxidative damage. In vivo, BACH1 overexpression worsened lung injury and apoptosis, while knockdown was protective. Immunohistochemistry showed BACH1 upregulation reduced phospho-STAT3 and SLC7A11 in injured tissue.</div></div><div><h3>Conclusion</h3><div>BACH1 drives ferroptosis-mediated LIRI via a KDM4C/PU.1/SHP1 axis, suppressing the STAT3/GPX4/SLC7A11/FTH1 pathway. Targeting BACH1 or its effectors offers therapeutic potential for LIRI prevention.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110669"},"PeriodicalIF":3.0,"publicationDate":"2025-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145450684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Emergence and characterization of lipidated β-lactamases 脂化β-内酰胺酶的出现和特性。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-11-03 DOI: 10.1016/j.abb.2025.110644

Thomas Smisek , Walter Fast , Christian P. Whitman

Since the discovery of penicillin, β-lactam antibiotics have been a mainstay for the treatment of bacterial infections. Resistance to β-lactam antibiotics via β-lactamase enzymes was identified before β-lactams even reached a clinical setting, and decades of use has only increased the risk posed by β-lactam resistance, largely driven by β-lactamase enzymes. While most β-lactamases are soluble periplasmic enzymes, a minority are membrane anchored lipoproteins. With the emergence and proliferation of the highly potent New Delhi metallo-β-lactamase (NDM) in the late 2000's, lipidated β-lactamases have catapulted from little more than biochemical curiosities, to key features of one of the most potent and prevalent antibiotic resistance enzymes. NDM is the most well-known lipidated β-lactamase. However, recent work highlights both emerging lipidated β-lactamases as well as the fact that lipidation may be more common in previously characterized β-lactamases than thought.

自从发现青霉素以来，β-内酰胺类抗生素一直是治疗细菌感染的主要药物。通过β-内酰胺酶对β-内酰胺类抗生素的耐药性在β-内酰胺类抗生素进入临床之前就已被发现，几十年的使用只会增加β-内酰胺类抗生素耐药的风险，这主要是由β-内酰胺酶驱动的。虽然大多数β-内酰胺酶是可溶性质周酶，但少数是膜锚定脂蛋白。随着高效的新德里金属β-内酰胺酶（NDM）在2000年代后期的出现和扩散，脂化β-内酰胺酶已经从仅仅是生物化学上的好奇心，一跃成为最有效和最普遍的抗生素抗性酶之一的关键特征。NDM是最著名的脂化β-内酰胺酶。然而，最近的工作强调了新兴的脂化β-内酰胺酶，以及脂化在以前表征的β-内酰胺酶中可能比想象的更常见的事实。

引用次数: 0

Substrate stiffness attenuates cardiomyocyte depolarization slope via sodium channel kinetics modulation 基底硬度通过钠通道动力学调节减弱心肌细胞去极化斜率。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-10-31 DOI: 10.1016/j.abb.2025.110668

Yuan Zhu , Sheng-an Su , Jixie Le , Yutao Xi , Meixiang Xiang

Background

The excessive deposition of extracellular matrix (ECM) components in cardiac tissue increases myocardial stiffness, contributing to diastolic dysfunction and arrhythmia risk. While this clinical association is established, the underlying electromechanical mechanisms remain elusive.

Methods

Using human and neonatal rat cardiomyocytes cultured on tunable 3D PDMS substrates replicating infarcted rat heart decellularized ECM (dECM) stiffness, we systematically investigated how ECM-mediated mechanical changes alter action potentials and sodium current dynamics, as well as Nav1.5 expression. 3D PDMS substrates were fabricated with stiffness values spanning the mechanical range of infarcted rat heart dECM (Young's modulus: ∼20–400 kPa; elastic modulus: ∼5–30 pN/nm). Human induced pluripotent stem cell-derived cardiomyocytes (15-day culture), neonatal rat cardiomyocytes (3-day culture) and human embryonic kidney 293 (24-h culture) cells stably expressing human Nav1.5 were cultured on the these PDMS substrates. Stiffness-dependent cellular electrophysiological effects were assessed using patch-clamp recordings. The gene and protein level changes were assessed by real-time quantitative polymerase chain reaction and immune blot.

Results

We found that evaluated substrate stiffness levels progressively reduced the AP upstroke slope, resulted in proarrhythmic AP morphologies characterized by increased AP instability and triangulation. Electrophysiological analysis revealed this mechanical modulation occurred through distinct sodium channel kinetic alterations: (1) a significant rightward-shifted voltage-dependent activation curve, and (2) a faster transition from a closed state to inactivation occurred, while maintaining unchanged current density, steady-state inactivation properties, and recovery time across stiffness conditions. This effect may arise from a conformation change in Nav1.5, since the expression and distribution of Nav1.5 has not altered across three PDMS groups.

Conclusions

In summary, substrate stiffening impaired cardiomyocyte depolarization and promoted conduction abnormalities via Nav1.5 dysfunction, suggesting a mechanoelectrical mechanism in ECM deposition related arrhythmogenesis.

背景：心肌组织中细胞外基质（ECM）成分的过度沉积会增加心肌硬度，导致舒张功能障碍和心律失常风险。虽然建立了这种临床联系，但潜在的机电机制仍然难以捉摸。方法：利用在可调3D PDMS基质上培养的人和新生大鼠心肌细胞复制梗死大鼠心脏脱细胞ECM （dECM）刚度，我们系统地研究了ECM介导的机械变化如何改变动作电位和钠电流动力学，以及Nav1.5的表达。三维PDMS基质的刚度值跨越梗死大鼠心脏dECM的力学范围（杨氏模量：~ 20-400 kPa；弹性模量：~ 5-30 pN/nm）。在这些PDMS基质上培养稳定表达人Nav1.5的人诱导多能干细胞来源的心肌细胞（培养15天）、新生大鼠心肌细胞（培养3天）和人胚胎肾293细胞（培养24小时）。使用膜片钳记录评估刚度依赖性细胞电生理效应。采用实时定量聚合酶链反应和免疫印迹法检测基因和蛋白水平变化。结果：我们发现评估的基底刚度水平逐渐降低了AP上冲程斜率，导致以AP不稳定性和三角化增加为特征的近心律失常AP形态。电生理分析表明，这种机械调节是通过不同的钠通道动力学改变发生的：(1)显著的向右移动的电压依赖激活曲线；(2)从闭合状态到失活的转变更快，同时保持不变的电流密度、稳态失活特性和恢复时间。这种影响可能是由Nav1.5的构象变化引起的，因为Nav1.5的表达和分布在三个PDMS组中没有改变。结论：综上所述，底物硬化损害心肌细胞去极化，并通过Nav1.5功能障碍促进传导异常，提示ECM沉积相关心律失常的机电机制。

{"title":"Substrate stiffness attenuates cardiomyocyte depolarization slope via sodium channel kinetics modulation","authors":"Yuan Zhu , Sheng-an Su , Jixie Le , Yutao Xi , Meixiang Xiang","doi":"10.1016/j.abb.2025.110668","DOIUrl":"10.1016/j.abb.2025.110668","url":null,"abstract":"<div><h3>Background</h3><div>The excessive deposition of extracellular matrix (ECM) components in cardiac tissue increases myocardial stiffness, contributing to diastolic dysfunction and arrhythmia risk. While this clinical association is established, the underlying electromechanical mechanisms remain elusive.</div></div><div><h3>Methods</h3><div>Using human and neonatal rat cardiomyocytes cultured on tunable 3D PDMS substrates replicating infarcted rat heart decellularized ECM (dECM) stiffness, we systematically investigated how ECM-mediated mechanical changes alter action potentials and sodium current dynamics, as well as Nav1.5 expression. 3D PDMS substrates were fabricated with stiffness values spanning the mechanical range of infarcted rat heart dECM (Young's modulus: ∼20–400 kPa; elastic modulus: ∼5–30 pN/nm). Human induced pluripotent stem cell-derived cardiomyocytes (15-day culture), neonatal rat cardiomyocytes (3-day culture) and human embryonic kidney 293 (24-h culture) cells stably expressing human Nav1.5 were cultured on the these PDMS substrates. Stiffness-dependent cellular electrophysiological effects were assessed using patch-clamp recordings. The gene and protein level changes were assessed by real-time quantitative polymerase chain reaction and immune blot.</div></div><div><h3>Results</h3><div>We found that evaluated substrate stiffness levels progressively reduced the AP upstroke slope, resulted in proarrhythmic AP morphologies characterized by increased AP instability and triangulation. Electrophysiological analysis revealed this mechanical modulation occurred through distinct sodium channel kinetic alterations: (1) a significant rightward-shifted voltage-dependent activation curve, and (2) a faster transition from a closed state to inactivation occurred, while maintaining unchanged current density, steady-state inactivation properties, and recovery time across stiffness conditions. This effect may arise from a conformation change in Nav1.5, since the expression and distribution of Nav1.5 has not altered across three PDMS groups.</div></div><div><h3>Conclusions</h3><div>In summary, substrate stiffening impaired cardiomyocyte depolarization and promoted conduction abnormalities via Nav1.5 dysfunction, suggesting a mechanoelectrical mechanism in ECM deposition related arrhythmogenesis.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110668"},"PeriodicalIF":3.0,"publicationDate":"2025-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145430219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

SIRT7 deficiency promoted cuproptosis-mediated mitochondrial dysfunction and inhibited malignant development of cervical cancer SIRT7缺失促进铜裂介导的线粒体功能障碍，抑制宫颈癌的恶性发展。

IF 3 3区生物学 Q2 BIOCHEMISTRY & MOLECULAR BIOLOGY

Archives of biochemistry and biophysics

Pub Date : 2025-10-29 DOI: 10.1016/j.abb.2025.110651

Qun Gao , Qi Wang , Yanjiao Hu , Fangjie Xin , Jie Chen , Sha Yu , Xinli Chen , Qingqing Lv , Baoxia Cui , Jun Jiao , Xinlin Jiao

Purpose

To investigate the impact of SIRT7 on the development of cervical cancer and its relationship with cuproptosis in cervical cancer.

Method

HeLa and SiHa cells were transfected with lentiviruses for SIRT7 overexpression and knockdown. The effects of SIRT7 on cervical cancer cell proliferation, apoptosis, invasion, and migration were analyzed using CCK8, plate cloning, flow cytometry, Transwell assays, and scratch assays. To verify the relationship between SIRT7 and cuproptosis, we utilized cuproptosis inhibitors and activators. Immunofluorescence, transmission electron microscope, flow cytometry, ELISA, and Western blot were used to analyze copper ion content, mitochondrial ultrastructure, cellular reactive oxygen species, mitochondrial membrane potential, pyruvate levels, cell viability and the cuproptosis-related proteins.

Results

SIRT7 enhanced the proliferation, migration, and invasion of HeLa and SiHa cells, inhibited apoptosis, and promoted cervical cancer growth. Knocking down SIRT7 caused cuproptosis of HeLa and SiHa cells, characterized by increased Cu²⁺ content, disrupted mitochondrial structure, decreased membrane potential, elevated ROS production, and upregulation of cuproptosis-related proteins SLC31A1 and HSP70, and downregulation of FDX1, LIAS and DLAT. Low SIRT7 expression's effect on cuproptosis was reduced by TTM. SIRT7 overexpression inhibited cuproptosis, unlike SIRT7 knockdown. SIRT7 overexpression's inhibitory effect on cuproptosis is altered by rhSLC31A1.

Conclusion

SIRT7 was recognized as an oncogene in cervical cancer, which boosted cervical cancer cell proliferation and invasion, lowered intracellular copper levels, and prevented cuproptosis. SIRT7 downregulation triggered cuproptosis, inhibiting tumor cell growth.

目的：探讨SIRT7对宫颈癌发生发展的影响及其与宫颈癌铜体畸形的关系。方法：用慢病毒转染Hela和SiHa细胞，进行SIRT7过表达和敲低。采用CCK8、平板克隆、流式细胞术、Transwell实验和划痕实验分析SIRT7对宫颈癌细胞增殖、凋亡、侵袭和迁移的影响。为了验证SIRT7与铜突起之间的关系，我们使用了铜突起抑制剂和活化剂。采用免疫荧光、透射电镜、流式细胞术、酶联免疫吸附法、免疫印迹法等检测各组铜离子含量、线粒体超微结构、细胞活性氧、线粒体膜电位、丙酮酸水平、细胞活力及铜脱落相关蛋白。结果：SIRT7增强HeLa和SiHa细胞的增殖、迁移和侵袭，抑制凋亡，抑制宫颈癌生长。敲除SIRT7导致HeLa和SiHa细胞铜变形，其特征是Cu2+含量增加，线粒体结构破坏，膜电位降低，ROS生成增加，铜变形蛋白SLC31A1和HSP70上调，FDX1、LIAS和DLAT下调。SIRT7低表达对铜生长的影响被TTM降低。与SIRT7敲低不同，SIRT7过表达抑制铜突起。SIRT7过表达对铜生长的抑制作用被rhSLC31A1改变。结论：SIRT7在宫颈癌中被认为是一种致癌基因，可促进宫颈癌细胞的增殖和侵袭，降低细胞内铜水平，防止铜沉降。SIRT7下调触发cuprotosis，抑制肿瘤细胞生长。

{"title":"SIRT7 deficiency promoted cuproptosis-mediated mitochondrial dysfunction and inhibited malignant development of cervical cancer","authors":"Qun Gao , Qi Wang , Yanjiao Hu , Fangjie Xin , Jie Chen , Sha Yu , Xinli Chen , Qingqing Lv , Baoxia Cui , Jun Jiao , Xinlin Jiao","doi":"10.1016/j.abb.2025.110651","DOIUrl":"10.1016/j.abb.2025.110651","url":null,"abstract":"<div><h3>Purpose</h3><div>To investigate the impact of SIRT7 on the development of cervical cancer and its relationship with cuproptosis in cervical cancer.</div></div><div><h3>Method</h3><div>HeLa and SiHa cells were transfected with lentiviruses for SIRT7 overexpression and knockdown. The effects of SIRT7 on cervical cancer cell proliferation, apoptosis, invasion, and migration were analyzed using CCK8, plate cloning, flow cytometry, Transwell assays, and scratch assays. To verify the relationship between SIRT7 and cuproptosis, we utilized cuproptosis inhibitors and activators. Immunofluorescence, transmission electron microscope, flow cytometry, ELISA, and Western blot were used to analyze copper ion content, mitochondrial ultrastructure, cellular reactive oxygen species, mitochondrial membrane potential, pyruvate levels, cell viability and the cuproptosis-related proteins.</div></div><div><h3>Results</h3><div>SIRT7 enhanced the proliferation, migration, and invasion of HeLa and SiHa cells, inhibited apoptosis, and promoted cervical cancer growth. Knocking down SIRT7 caused cuproptosis of HeLa and SiHa cells, characterized by increased Cu<sup>2+</sup> content, disrupted mitochondrial structure, decreased membrane potential, elevated ROS production, and upregulation of cuproptosis-related proteins SLC31A1 and HSP70, and downregulation of FDX1, LIAS and DLAT. Low SIRT7 expression's effect on cuproptosis was reduced by TTM. SIRT7 overexpression inhibited cuproptosis, unlike SIRT7 knockdown. SIRT7 overexpression's inhibitory effect on cuproptosis is altered by rhSLC31A1.</div></div><div><h3>Conclusion</h3><div>SIRT7 was recognized as an oncogene in cervical cancer, which boosted cervical cancer cell proliferation and invasion, lowered intracellular copper levels, and prevented cuproptosis. SIRT7 downregulation triggered cuproptosis, inhibiting tumor cell growth.</div></div>","PeriodicalId":8174,"journal":{"name":"Archives of biochemistry and biophysics","volume":"775 ","pages":"Article 110651"},"PeriodicalIF":3.0,"publicationDate":"2025-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145407881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0