Effects of cisplatin on mitochondrial function and autophagy-related proteins in skeletal muscle of rats

Cisplatin-Induced Muscle Wasting and Atrophy: Molecular Mechanism and Potential Therapeutic Interventions

Platinum-based chemotherapeutics, particularly cisplatin, are crucial in the treatment of various malignancies due to their strong antitumor effects. However, a significant side effect of cisplatin is muscle atrophy, which severely impairs physical strength, diminishes quality of life and complicates cancer therapy. Cisplatin-induced muscle wasting arises from a complex interplay of enhanced proteolysis, reduced muscle protein synthesis and systemic inflammation. Understanding the underlying molecular mechanisms of muscle atrophy is vital for identifying new therapeutic targets. This review systematically explores molecular-based therapies and plant-derived natural compounds, providing a comprehensive overview of their efficacy in vivo and in vitro for preventing cisplatin-induced muscle atrophy. Both molecular-based therapies and plant-derived natural compounds present promising strategies for mitigating cisplatin-induced muscle atrophy. Ghrelin, growth hormone secretagogues and testosterone stimulate anabolic pathways and reduce muscle degradation, whereas natural compounds like capsaicin and naringenin exert protective effects by reducing inflammation and oxidative stress. A better understanding of the pathophysiology of muscle atrophy, combined with optimized therapeutic applications, may facilitate the clinical translation of these interventions to improve outcomes for cancer patients undergoing chemotherapy.

Synergistic anti-cancer effects of metformin and cisplatin on YD-9 oral squamous carcinoma cells via AMPK pathway

OBJECTIVE

This study evaluated whether hypoglycemic drug metformin enhances the anti-cancer effects of cisplatin in YD-9 cells.

METHODOLOGY

YD-9 cells, derived from oral mucosal squamous cell carcinoma of oral mucosa, were used to assess the combined effects of metformin and cisplatin by means of MTT assay, live and dead cell staining, and colony formation assays to evaluate cell viability and proliferation. Reactive oxygen species level was measured using a Muse cell analyzer. Apoptosis, epithelial-mesenchymal transition, and related molecular pathways were analyzed by western blot. Wound healing assays and Transwell migration assays examined cell migration, whereas monophosphate-activated protein kinase inhibitor Compound C, was utilized to investigate the AMPK pathway.

RESULTS

Sequential treatment of YD-9 cells with metformin and cisplatin resulted in decreased cell viability and proliferation, increased ROS levels, and elevated apoptosis compared with the individual drugs. Moreover, the treatment inhibited EMT, wound healing, and cell migration. These results correlated with increased AMPK phosphorylation, a key regulator of cellular energy homeostasis. Introduction of Compound C pre-treatment upregulated N-cadherin and α-smooth muscle actin along with enhanced cell migration.

CONCLUSION

This study found synergism in anti-cancer effects between metformin and cisplatin. Additionally, introduction of Compound C confirmed that EMT inhibition is AMPK dependent. These findings indicate the potential use of metformin as an adjunct drug in anti-cancer treatments, warranting further investigation.

Exercise alleviates cisplatin-induced toxicity in the hippocampus of mice by inhibiting neuroinflammation and improving synaptic plasticity

Chemotherapy-induced cognitive impairment is recognized as the most typical symptom in patients with cancer that occurs during and following the chemotherapy treatment. Recently many studies focused on pharmaceutical strategies to control the chemotherapy side effects, however it is far from satisfactory. There may be a need for more effective treatment options. The aim of this study was to investigate the protective effect of exercise on cisplatin-induced neurotoxicity. Eightweek- old C57BL6 mice were separated into three group: normal control (CON, n = 8); cisplatin injection control (Cis-CON, n = 8); cisplatin with aerobic exercise (Cis-EXE, n = 8). Cisplatin was administered intraperitoneally at a dose of 3.5 mg/kg/day. The Cis-EXE group exercise by treadmill running (14-16 m/min for 45 min daily, 3 times/ week) for 12 weeks. Compared to the CON group, the cisplatin injection groups showed significant decrease in body weight and food intake, indicating successful induction of cisplatin toxicity. The Cis-CON group showed significantly increased levels of pro-inflammatory cytokines including IL-6, IL-1β, and TNF-α in the hippocampus, while the Cis-EXE group was significantly decreased in the expression of IL- 6, IL-1β, and TNF-α. In addition, compared to the CON group, the levels of synapserelated proteins including synapsin-1 and -2 were significantly reduced in the Cis- CON group, and there was a significant difference between the Cis-CON and Cis-EXE groups. Antioxidant and apoptosis factors were significantly improved in the Cis-EXE group compared with the Cis-CON group. This study suggest that exercise could be meaningful approach to prevent or improve cisplatin-induced cognitive impairment.

Mitochondrial dysfunction and skeletal muscle atrophy: Causes, mechanisms, and treatment strategies

Skeletal muscle, which accounts for approximately 40% of total body weight, is one of the most dynamic and plastic tissues in the human body and plays a vital role in movement, posture and force production. More than just a component of the locomotor system, skeletal muscle functions as an endocrine organ capable of producing and secreting hundreds of bioactive molecules. Therefore, maintaining healthy skeletal muscles is crucial for supporting overall body health. Various pathological conditions, such as prolonged immobilization, cachexia, aging, drug-induced toxicity, and cardiovascular diseases (CVDs), can disrupt the balance between muscle protein synthesis and degradation, leading to skeletal muscle atrophy. Mitochondrial dysfunction is a major contributing mechanism to skeletal muscle atrophy, as it plays crucial roles in various biological processes, including energy production, metabolic flexibility, maintenance of redox homeostasis, and regulation of apoptosis. In this review, we critically examine recent knowledge regarding the causes of muscle atrophy (disuse, cachexia, aging, etc.) and its contribution to CVDs. Additionally, we highlight the mitochondrial signaling pathways involvement to skeletal muscle atrophy, such as the ubiquitin-proteasome system, autophagy and mitophagy, mitochondrial fission-fusion, and mitochondrial biogenesis. Furthermore, we discuss current strategies, including exercise, mitochondria-targeted antioxidants, in vivo transfection of PGC-1α, and the potential use of mitochondrial transplantation as a possible therapeutic approach.

Adverse effects of systemic cancer therapy on skeletal muscle: myotoxicity comes out of the closet

PURPOSE OF REVIEW

Systemic cancer therapy-associated skeletal muscle wasting is emerging as a powerful impetus to the overall loss of skeletal muscle experienced by patients with cancer. This review explores the clinical magnitude and biological mechanisms of muscle wasting during systemic cancer therapy to illuminate this adverse effect. Emerging strategies for mitigation are also discussed.

RECENT FINDINGS

Clinical findings include precise, specific measures of muscle loss over the course of chemotherapy, targeted therapy and immunotherapy. All these therapeutic classes associate with quantitatively important muscle loss, independent of tumor response. Parallel experimental studies provide understanding of the specific molecular basis of wasting, which can include inhibition of protein synthesis, proliferation and differentiation, and activation of inflammation, reactive oxygen species, autophagy, mitophagy, apoptosis, protein catabolism, fibrosis and steatosis in muscle. Strategies to mitigate these muscle-specific adverse effects of cancer therapy remain in the earliest stages of development.

SUMMARY

The adverse side effect of cancer therapy on skeletal muscle has been largely ignored in the development of cancer therapeutics. Given the extent to which loss of muscle mass and function can bear on patients' function and quality of life, protection/mitigation of these side effects is a research priority.

Capsaicin alleviates cisplatin-induced muscle loss and atrophy in vitro and in vivo

BACKGROUND

Cisplatin (CP) is a widely used chemotherapeutic drug with subsequent adverse effects on different organs and tissues including skeletal muscle loss and atrophy as the most common clinical symptoms. The molecular mechanism of cisplatin-induced muscle atrophy is not clearly understood. However, recent significant advances indicate that it is related to an imbalance in both the protein status and apoptosis. Capsaicin (CAP) is one of the major ingredients in chilli peppers. It is a valuable pharmacological agent with several therapeutic applications in controlling pain and inflammation with particular therapeutic potential in muscle atrophy. However, the mechanisms underlying its protective effects against cisplatin-induced muscle loss and atrophy remain largely unknown. This study aims to investigate capsaicin's beneficial effects on cisplatin-induced muscle loss and atrophy in vitro and in vivo.

METHODS

The anti-muscle-atrophic effect of capsaicin on cisplatin-induced muscle loss was investigated using in vivo and in vitro studies. By using the pretreatment model, pretreated capsaicin for 24 h and treated with cisplatin for 48 h, we utilized a C₂ C₁₂ myotube formation model where cell viability analysis, immunofluorescence, and protein expression were measured to investigate the effect of capsaicin in hampering cisplatin-induced muscle atrophy. C57BL/6 mice were administered capsaicin (10, 40 mg/kg BW) as a pretreatment for 5 weeks and cisplatin (3 mg/kg BW) for seven consecutively days to assess muscle atrophy in an animal model for protein and oxidative stress examination, and the grip strength was tested to evaluate the muscle strength.

RESULTS

Our study results indicated that cisplatin caused lower cell viability and showed a subset of hallmark signs typically recognized during atrophy, including severe reduction in the myotube diameter, repression of Akt, and mTOR protein expression. However, pretreatment with capsaicin could ameliorate cisplatin-induced muscle atrophy by up-regulating the protein synthesis in skeletal muscle as well as down-regulating the markers of protein degradation. Additionally, capsaicin was able to downregulate the protein expression of apoptosis-related markers, activated TRPV1 and autophagy progress modulation and the recovery of lysosome function. In vivo, capsaicin could relieve oxidative stress and cytokine secretion while modulating autophagy-related lysosome fusion, improving grip strength, and alleviating cisplatin-induced body weight loss and gastrocnemius atrophy.

CONCLUSIONS

These findings suggest that capsaicin can restore cisplatin-induced imbalance between protein synthesis and protein degradation pathways and it may have protective effects against cisplatin-induced muscle atrophy.