Pathogenesis, Intervention, and Current Status of Drug Development for Sarcopenia: A Review

Dietary advanced glycation end-products exacerbate sarcopenia onset by activating apoptosis through PRMT1-mediated CRTC3 arginine methylation

BACKGROUND

Sarcopenia, the age-related decline in muscle mass and function, poses a major health risk to the elderly population. Although dietary advanced glycation end-products (AGEs) have been implicated in worsening sarcopenia, the precise molecular mechanisms remain unclear.

METHODS

A sarcopenia animal model was established by feeding a high AGE diet to C57BL/6 mice. Muscle function and mass were assessed using grip strength tests, and rotarod tests. Proteomic analysis was used to identify differentially expressed proteins. Immunoprecipitation, mass spectrometry, and co-immunoprecipitation were employed to investigate protein interactions both in vivo and in vitro. Quantitative reverse transcription PCR and Western blotting were conducted to measure gene and protein expression levels.

RESULTS

Our results revealed that dietary AGEs accelerated the onset of sarcopenia in mice by triggering apoptosis. Proteomic analysis showed a marked upregulation of protein arginine methyltransferase 1 (PRMT1) in the muscle tissues of mice fed a high AGE diet. PRMT1 mediated the arginine methylation of CREB-regulated transcription coactivator 3 (CRTC3) at the R534 site within its transactivation domain, leading to CRTC3 activation. The activated CRTC3, together with Forkhead box O3a (FOXO3a), transactivated the BAX (BCL2 associated X) gene, initiating Bax downstream signaling, promoting apoptosis in muscle cells, and contributing to muscle atrophy. Inhibition of PRMT1 prevented CRTC3 methylation and suppressed Bax-mediated apoptotic signaling in vitro. Moreover, in vivo treatment with PRMT1 and Bax inhibitors significantly attenuated AGE-induced sarcopenia in mice.

CONCLUSION

PRMT1-mediated CRTC3 arginine methylation plays a critical role in AGE-induced sarcopenia and suggests potential therapeutic targets for preventing sarcopenia progression.

Impact of Hospitalization on Sarcopenia, NADPH-Oxidase 2, Oxidative Stress, and Low-Grade Endotoxemia in Elderly Patients

BACKGROUND

Hospitalization in older adults often worsens sarcopenia due to prolonged bed rest, poor nutrition, and inactivity. This study examined how hospitalization impacts muscle mass, focusing on oxidative stress and gut-derived endotoxemia.

METHODS

Thirty-one hospitalized older adults were compared with 31 outpatients. Ultrasound was used to measure the thickness of the rectus femoris (RF), intercostal, and diaphragmatic muscles at admission and discharge. Serum levels of LPS, zonulin, sNOX2-dp, and H2O2 were also assessed.

RESULTS

Hospitalized patients had higher serum levels of sNOX2-dp, H2O2, LPS, and zonulin than outpatients. In hospitalized patients, significant increases were observed at discharge compared to admission levels in sNOX2-dp (20.9 ± 6.5 to 23.8 ± 7.5 pg/mL; p = 0.004), H2O2 (24.4 ± 9.8 to 32.8 ± 14.5 µM; p = 0.01), LPS (30.4 ± 12.6 to 43.3 ± 16.35 pg/mL; p < 0.001), and zonulin (2.06 ± 1.23 to 2.95 ± 1.33 ng/mL; p < 0.001). Ultrasound data revealed a reduction in RF muscle thickness (-35%) (0.58 ± 0.29 to 0.38 ± 0.31 cm, p < 0.001), intercostal muscle thickness (-28%) (0.22 ± 0.08 to 0.16 ± 0.06 cm, p < 0.001), and diaphragmatic muscle thickness (-26%) (0.19 ± 0.06 to 0.14 ± 0.04 cm, p < 0.001) at discharge compared to admission. Additionally, muscle strength, measured using the hand-grip test, showed a 25% reduction. Regression analysis revealed correlations between RF muscle loss and increases in sNOX2-dp and H2O2, as well as between NOX2, H2O2, and LPS with zonulin.

CONCLUSIONS

Hospitalization in older adult patients elevates NOX2 blood levels, correlating with reduced muscle mass. Increased low-grade endotoxemia may trigger NOX2 activation, generating oxidative stress that accelerates muscle degeneration and can lead to sarcopenia.

Effect and mechanism of miRNA-144-5p-regulated autophagy in older adults with Sarcopenia

BACKGROUND

Advanced aging invariably triggers an overabundance of apoptosis, stemming from diminished autophagy or a disarray in cellular autophagic processes. This, in turn, leads to an accelerated breakdown of muscle proteins, which exacerbates the ongoing deterioration of skeletal muscle and intensifies the severity of senile sarcopenia. This study aimed to investigate the role and mechanism of miRNA-regulated autophagy in senile sarcopenia.

METHODS

The miRNAs associated with sarcopenia were screened, and the target genes of significant miRNAs were predicted. The effects of significantly differentially expressed miRNA-144-5p on cell aging and autophagy were validated in vivo and in vitro.

RESULTS

The inhibition of miR-144-5p enhanced the multiplication of mouse myoblasts, increased the expression of MHC and autophagic markers LC3II/LC3I and Beclin-1, facilitated the formation of autophagosomes in mouse myoblasts, and reduced the number of aging cells and the expression of senescence-related proteins acetylated p53, p53, and p21 expression in mouse myoblasts. miR-144-5p affects myoblast senescence, myogenic differentiation, and autophagy by regulating the downstream target gene, Atg2A. Inhibiting miR-144-5p markedly increased the grip strength of the posterior limb in old mice, and the CSA of old mice and young mice was also markedly increased.

CONCLUSION

All experiments have demonstrated that miRNA-144-5p has a significant impact on the regulation of autophagy and the development of senile sarcopenia.

Insights into sarcopenia awareness among trainee physicians: a survey-based analysis of a university hospital, Thailand

Background

Sarcopenia is associated with a decline in functionality and disability among older adults. Extensive research has been conducted on the subject matter of sarcopenia; nevertheless, there is a paucity of studies documenting the extent to which practicing physicians are integrating sarcopenia into their clinical practice in the Asian context.

Objectives

To examine trainee physicians' attitude and knowledge in sarcopenia and factors associated with higher scores on knowledge in sarcopenia.

Methods

An electronic survey of trainee physicians of the Faculty of Medicine, Khon Kaen University, Thailand was conducted from November 2022 to December 2023. The survey consisted of questionnaires designed to assess both attitude and knowledge toward sarcopenia. All trainees were invited to participate, and the completed questionnaires were subsequently returned to the researchers for analysis.

Results

A total of 211 trainees enrolled; most of them were familiar with "sarcopenia" (70.1%) but lack of confidence in diagnosis, prevention, and management. The total scores on general knowledge about sarcopenia were 22 out of 30 (73.3%). They scored well in the area of "etiology" (75%) and "terminology and importance" (70%) but fair in "diagnosis" (62.5%) and "management and prevention" (62.5%). The lower age of the trainee physicians, increased years of practice, and "training in internal medicine" were associated with higher scores.

Conclusions

Trainee physicians were aware of the term "sarcopenia" but had limited knowledge in diagnosis, prevention, and management. Certain factors related to better scores on the knowledge evaluation were identified.

Ginsenoside Rc prevents dexamethasone-induced muscle atrophy and enhances muscle strength and motor function

Background

A decline in muscle mass and function can impact the health, disease vulnerability, and mortality of older adults. Prolonged use of high doses of glucocorticoids, such as dexamethasone (DEX), can cause muscle wasting and reduced strength. Ginsenoside Rc (gRc) has been shown to protect muscles by activating the PGC-1α pathway and improving mitochondrial function. The effects of gRc on muscle atrophy and function in mice are not fully understood.

Methods and results

The study discovered that gRc prevented the DEX-induced decrease in viability of C2C12 myoblasts and myotubes. Furthermore, gRc inhibited myotube degradation and the upregulation of muscle degradation proteins induced by DEX. Transcriptome analysis of myotubes showed that gRc enhances muscle generation processes while suppressing the TGF-β pathway and oxidative stress response. In mice, gRc effectively reversed the reductions in body weight, muscle mass, and muscle fibers caused by DEX. Furthermore, gRc significantly enhanced muscle strength and exercise capacity. Docking and transcriptome analyses indicated that gRc may act as a competitive inhibitor of DEX at the glucocorticoid receptor, potentially preventing muscle loss.

Conclusion

The study suggests that gRc can prevent DEX-induced muscle wasting and weakness. Consequently, it may be a viable treatment option for sarcopenia and muscle-related disorders in various medical conditions.

Fermented antler extract attenuates muscle atrophy by regulating the PI3K/Akt pathway and inflammatory response in immobilization-treated C57BL/6J mice

Muscle atrophy or muscle wasting, which is featured by reduced muscle function and mass, typically results from disuse, aging, and chronic diseases. The deer antler, which refers to the young and non-ossified antlers of various species of deer-related animals, is not fully calcified and comprises of densely growing hair. Here, we investigated whether Bacillus subtilis-fermented antler extract (FAE) inhibits immobilization-induced muscle atrophy in C57BL/6J mice. Oral administration of FAE increased grip strength, exercise performance, muscle mass, and volume in mice. FAE stimulated the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, enhancing the mammalian target of rapamycin pathway for muscle synthesis. FAE phosphorylated Forkhead box O3 and downregulated muscle RING finger-1 and atrogin-1 for proteolysis. FAE inhibited the mRNA expression of tumor necrosis factor alpha and interleukin-6 through nuclear factor kappa B. Consequently, FAE attenuated muscle atrophy by regulating the PI3K/Akt pathway and inflammation.

Association between possible sarcopenia, all-cause mortality, and adverse health outcomes in community-dwelling older adults in China

The relationship between possible sarcopenia and mortality remains ambiguous within Asian populations. To clarify this, we investigated the association in older adults residing in Chinese communities. Utilizing data from the China Health and Retirement Longitudinal Study, this population-based cohort study included individuals aged ≥ 60 years, followed from 2011 to 2012 through 2020. Possible sarcopenia was defined in accordance with the Asian Working Group on Sarcopenia 2019 criteria, and Cox proportional hazards regression was used to analyze its impact on mortality, while exploratory analyses were conducted to investigate the associations of possible sarcopenia with chronic diseases, functional independence, and hospitalization frequency. The study encompassed 5,160 participants (median age: 66 years), nearly half of whom (48.8%) were identified with possible sarcopenia. Over a 9-year follow-up period, there were 1216 recorded deaths. Analysis indicated that individuals with possible sarcopenia faced a significantly elevated mortality risk compared to their counterparts (HR: 1.79, 95% CI: 1.58-2.03; P < 0.001). Further, subgroup analyses confirmed a strong association between possible sarcopenia and all-cause mortality across various subgroups, including those related to sex, obesity status, and living environment. Additionally, exploratory analyses revealed that possible sarcopenia was significantly associated with an increased likelihood of heart disease (OR = 1.18, 95% CI: 1.03-1.34, P = 0.014) and stroke (OR = 1.41, 95% CI: 1.19-1.68, P < 0.001), as well as reduced functional independence (β = -0.17, 95% CI: -0.24--0.10, P < 0.001). Possible sarcopenia was also associated with a higher frequency of hospitalizations at baseline (Exp(β) = 1.50, 95% CI: 1.25-1.81, P < 0.001), although this association was no longer significant during the follow-up period. In conclusion, in Chinese community-dwelling older adults, possible sarcopenia was associated with an increased risk of all-cause mortality, several chronic diseases, and functional dependence. Thus, alleviating or preventing possible sarcopenia may improve health outcomes and extend the lifespan of these individuals.

Protective Effects of Cervus elaphus and Eucommia ulmoides Mixture (KGC01CE) on Muscle Loss and Function in Aged Rats

Sarcopenia is a condition characterized by a progressive loss of muscle mass and function which are influenced by certain factors such as aging, nutritional deficiencies, and chronic diseases. Despite numerous efforts to prevent or treat sarcopenia, effective therapeutic options for this disease remain limited. This study aims to evaluate the effects of KGC01CE treatment, a mixture of Cervus elaphus (Ce) and Eucommia ulmoides (Eu), which are well-known traditional herbal medicines in Asia, on age-related muscle loss and functional decline in aged rats. KGC01CE has been found to be more effective than the individual extracts in inhibiting dexamethasone (DEX)-induced muscle atrophy and improving muscle mass and grip strength in C2C12 cells and aged rats. Moreover, animal studies were conducted to determine the minimum effective dose, and a 12-week oral administration of KGC01CE treatment at doses of 50, 100, and 200 mg/kg to 15-month-old aged rats resulted in a dose-dependent increase in lean mass, muscle mass, grip strength, and muscle cross-sectional area (CSA), which had decreased due to aging. Furthermore, it was shown that KGC01CE activated the phosphatidylinositol 3-kinase (PI3K)/Akt pathway and inhibited the expression of muscle-degrading proteins MuRF, Atrogin-1, and myostatin. These results suggest that KGC01CE treatment may effectively prevent muscle loss and functional decline, providing a novel therapeutic strategy for sarcopenia.

Nurses' Perspectives and Understanding of Sarcopenia in a Tertiary Care Hospital

Background

Sarcopenia is prevalent in older adults. It is essential for nurses to sustain updated information regarding the knowledge of sarcopenia, particularly in relation to approaches to diagnosing and addressing sarcopenia. However, there are limited studies examining the attitudes and awareness of nurses in relation to this condition.

Objective

To assess the attitude and knowledge of nurses regarding sarcopenia and correlation between positive attitude and scores on knowledge.

Materials and Methods

An electronic survey was carried out among the nurses of the Faculty of Medicine, Khon Kaen University, Thailand, during November 2022 and January 2024. This survey encompassed questionnaires aimed at evaluating the nurses' perspectives and understanding of sarcopenia. The participants were invited to complete the survey, and they were returned to the researchers for analysis.

Results

A total of 231 nurses were recruited (response rate 46.2%). Only 58.4% of them were familiar with "sarcopenia," while only 16% had confidence in diagnosing it. For general knowledge, they achieved a total score of 19/30 (63.3%). They demonstrated proficiency in "etiology" (75%), while their performance was fair in "management and prevention" (62.5%) and low in "terminology & importance" (50%) and "diagnosis" (50%). The correlation between positive attitude and knowledge on sarcopenia was 0.22 (p < 0.05).

Conclusion

Nurses exhibited a reduced awareness regarding "sarcopenia." Their comprehension about terminology, diagnosis, prevention, and management of this condition was limited. There was a weak correlation between positive attitude and knowledge. The findings emphasize the essentiality of augmenting the educational programs to enhance the recognition of sarcopenia among nurses.

Evaluation of Withania somnifera (L.) Dunal (Ashwagandha) on Physical Performance, Biomarkers of Inflammation, and Muscle Status in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled Study

BACKGROUND

Sarcopenia is associated with chronic inflammation, a sedentary lifestyle, and ageing. However, there exists no drug, which is safe and effective for long-term use. Ashwagandha (Withaniasomnifera (L.) Dunal) has the potential to fill this therapeutic gap based on its efficacy and safety profile; hence, the present study was planned to evaluate its effect on inflammatory biomarkers and muscle status in healthy volunteers.

METHODOLOGY

A prospective, double-blind, randomized, placebo-controlled clinical study was conducted to evaluate the effects of Ashwagandha extract in healthy volunteers (February 2021 to May 2022) who received either Ashwagandha extract tablets 250 mg or a placebo twice daily for 60 days. The physical performance on a bicycle ergometer, inflammatory/muscle status biomarkers, body composition, reaction time, hemogram, and organ function tests was assessed at baseline, day 30, and day 60.

RESULTS

In the Ashwagandha group, there was a statistically significant (p<0.05) improvement in total distance travelled (Ashwagandha 2.85 ± 0.54 km vs placebo 2.16 ± 0.62 km), average speed achieved (Ashwagandha 25.6 ± 5.7 km/hour vs placebo 22.2 ± 5.48 km/hour) on a bicycle ergometer from the baseline visit (V3) to the last visit (V7) as compared to the placebo group. The observations on hand-grip strength, back-leg press, skeletal muscle mass, and VO2 max showed an increasing trend from V3 to V7, whereas the results of the three inflammatory markers (hs-C-reactive protein (CRP) mg/L; IL-6; TNF-alpha ) and the muscle marker (myostatin) revealed a decreasing trend from V3 to V7 in the Ashwagandha group. Ashwagandha extract was found to be safe in healthy volunteers as evidenced by the clinical profile, laboratory investigations, and reaction time test.

CONCLUSION

Ashwagandha extract supplementation was safe and effective in enhancing physical performance and strengthening muscle mass and could be a potential candidate for treating sarcopenia.

Exploring neuronal mechanisms of osteosarcopenia in older adults

Until recently, research on the pathogenesis and treatment of osteoporosis and sarcopenia has primarily focused on local and systemic humoral mechanisms, often overlooking neuronal mechanisms. However, there is a growing body of literature on the neuronal regulation of bone and skeletal muscle structure and function, which may provide insights into the pathogenesis of osteosarcopenia. This review aims to integrate these neuronal regulatory mechanisms to form a comprehensive understanding and inspire future research that could uncover novel strategies for preventing and treating osteosarcopenia. Specifically, the review explores the functional adaptation of weight-bearing bone to mechanical loading throughout evolutionary development, from Wolff's law and Frost's mechanostat theory to the mosaic hypothesis, which emphasizes neuronal regulation. The recently introduced bone osteoregulation reflex points to the importance of the osteocytic mechanoreceptive network as a receptor in this neuronal regulation mechanism. Finally, the review focuses on the bone myoregulation reflex, which is known as a mechanism by which bone loading regulates muscle functions neuronally. Considering the ageing-related regressive changes in the nerve fibres that provide both structural and functional regulation in bone and skeletal muscle tissue and the bone and muscle tissues they innervate, it is suggested that neuronal mechanisms might play a central role in explaining osteosarcopenia in older adults.

Harnessing immunomodulation to combat sarcopenia: current insights and possible approaches

Sarcopenia is a complex age-associated syndrome of progressive loss of muscle mass and strength. Although this condition is influenced by many factors, age-related changes in immune function including immune cell dynamics, and chronic inflammation contribute to its progression. The complex interplay between the immune system, gut-muscle axis, and autophagy further underscores their important roles in sarcopenia pathogenesis. Immunomodulation has emerged as a promising strategy to counteract sarcopenia. Traditional management approaches to treat sarcopenia including physical exercise and nutritional supplementation, and the emerging technologies of biophysical stimulation demonstrated the importance of immunomodulation and regulation of macrophages and T cells and reduction of chronic inflammation. Treatments to alleviate low-grade inflammation in older adults by modulating gut microbial composition and diversity further combat sarcopenia. Furthermore, some pharmacological interventions, nano-medicine, and cell therapies targeting muscle, gut microbiota, or autophagy present additional avenues for immunomodulation in sarcopenia. This narrative review explores the immunological underpinnings of sarcopenia, elucidating the relationship between the immune system and muscle during ageing. Additionally, the review discusses new areas such as the gut-muscle axis and autophagy, which bridge immune system function and muscle health. Insights into current and potential approaches for sarcopenia management through modulation of the immune system are provided, along with suggestions for future research directions and therapeutic strategies. We aim to guide further investigation into clinical immunological biomarkers and identify indicators for sarcopenia diagnosis and potential treatment targets to combat this condition. We also aim to draw attention to the importance of considering immunomodulation in the clinical management of sarcopenia.

Assessment of the Daily Living Activities of Older People (2004-2023): A Bibliometric and Visual Analysis

With a rapidly aging global population, comprehending the risks associated with older people's activities of daily living is increasingly important; yet, interdisciplinary analyses remain rare. By providing a bibliometric overview of the capability risks associated with older people's activities of daily living, in order to identify prevailing trends and future directions in the field, the study aims to fill this gap. Using CiteSpace software to analyze data from 928 articles published between 2004 and 2023, the study results demonstrate the growing interest in the capability risks of older people's activities of daily living, with the United States leading in the number of publications, and geriatrics emerging as the dominant discipline. Notably, Institut National de la Sante et de la Recherche Medicale (Inserm) in France emerges as a pivotal contributor in the field. Key research topics encompass risk factors associated with a decline in daily activities and disease-related studies, with emerging trends in cognitive function and instrumental activity research. Future research should prioritize the development of predictive mechanisms for daily living trends, exploration of caregiving solutions, and promotion of interdisciplinary collaboration. This study highlights promising avenues for further research, emphasizing the importance of predictive modeling, innovative caregiving strategies, and interdisciplinary cooperation in addressing capability risks in the activities of daily living of older people.

Sarcopenia in gynaecological cancers

Gynaecological cancers (GCs) comprise a group of cancers that originate in the female reproductive organs. Each GC is unique, with different signs and symptoms, risk factors and therapeutic strategies. Worldwide, the majority of GCs are still associated with high mortality rates, especially ovarian, due to difficulty in early detection. Despite numerous studies on the underlying pathophysiology, research in the field of GCs poses unique scientific and technological challenges. These challenges require a concerted multi- and inter-disciplinary effort by the clinical, scientific and research communities to accelerate the advancement of prognostic, diagnostic, and therapeutic approaches. Sarcopenia is a multifactorial disease which leads to the systemic loss of skeletal muscle mass and function. It can be caused by malignancies, as well as due to malnutrition, physical inactivity, ageing and neuromuscular, inflammatory, and/or endocrine diseases. Anorexia and systemic inflammation can shift the metabolic balance of patients with cancer cachexia towards catabolism of skeletal muscle, and hence sarcopenia. Therefore, sarcopenia is considered as an indicator of poor general health status, as well as the possible indicator of advanced cancer. There is a growing body of evidence showing the prognostic significance of sarcopenia in various cancers, including GCs. This review will outline the clinical importance of sarcopenia in patients with GCs.

Definition, diagnosis, and treatment of respiratory sarcopenia

PURPOSE OF REVIEW

Skeletal muscle weakness and wasting also occurs in the respiratory muscles, called respiratory sarcopenia. Respiratory sarcopenia may lead to worse clinical indicators and outcomes. We present a novel definition and diagnostic criteria for respiratory sarcopenia, summarize recent reports on the association between respiratory sarcopenia, physical and nutritional status, and clinical outcomes, and provide suggestions for the prevention and treatment of respiratory sarcopenia.

RECENT FINDINGS

Recently, a novel definition and diagnostic criteria for respiratory sarcopenia have been prepared. Respiratory sarcopenia is defined as a condition in which there is both low respiratory muscle strength and low respiratory muscle mass. Respiratory muscle strength, respiratory muscle mass, and appendicular skeletal muscle mass are used to diagnose respiratory sarcopenia. Currently, it is challenging to definitively diagnose respiratory sarcopenia due to the difficulty in accurately determining low respiratory muscle mass. Decreased respiratory muscle strength and respiratory muscle mass are associated with lower physical and nutritional status and poorer clinical outcomes. Exercise interventions, especially respiratory muscle training, nutritional interventions, and their combinations may effectively treat respiratory sarcopenia. Preventive interventions for respiratory sarcopenia are unclear.

SUMMARY

The novel definition and diagnostic criteria will contribute to promoting the assessment and intervention of respiratory sarcopenia.

Advances in sarcopenia: mechanisms, therapeutic targets, and intervention strategies

Sarcopenia is a multifactorial condition characterized by loss of muscle mass. It poses significant health risks in older adults worldwide. Both pharmacological and non-pharmacological approaches are reported to address this disease. Certain dietary patterns, such as adequate energy intake and essential amino acids, have shown positive outcomes in preserving muscle function. Various medications, including myostatin inhibitors, growth hormones, and activin type II receptor inhibitors, have been evaluated for their effectiveness in managing sarcopenia. However, it is important to consider the variable efficacy and potential side effects associated with these treatments. There are currently no drugs approved by the Food and Drug Administration for sarcopenia. The ongoing research aims to develop more effective strategies in the future. Our review of research on disease mechanisms and drug development will be a valuable contribution to future research endeavors.

Role of PPARα in inflammatory response of C2C12 myotubes

Recent studies have shown a role of inflammation in muscle atrophy and sarcopenia. However, no anti-inflammatory pharmacotherapy has been established for the treatment of sarcopenia. Here, we investigate the potential role of PPARα and its ligands on inflammatory response and PGC-1α gene expression in LPS-treated C2C12 myotubes. Knockdown of PPARα, whose expression was upregulated upon differentiation, augmented IL-6 or TNFα gene expression. Conversely, PPARα overexpression or its activation by ligands suppressed 2-h LPS-induced cytokine expression, with pemafibrate attenuating NF-κB or STAT3 phosphorylation. Of note, reduction of PGC-1α gene expression by LPS treatment for 24 hours was partially reversed by fenofibrate. Our data demonstrate a critical inhibitory role of PPARα in inflammatory response of C2C12 myotubes and suggest a future possibility of PPARα ligands as a candidate for anti-inflammatory therapy against sarcopenia.

Cross-Disciplinary Approach of Adrenal Tumors: Insights into Primary Aldosteronism-Related Mineral Metabolism Status and Osteoporotic Fracture Risk

Our objective was to overview the novel aspects in the field of adrenal gland neoplasms, namely, the management of bone status with respect to primary aldosteronism (PA). In the current narrative review, a PubMed study was conducted from inception until June 2023. The inclusion criteria were: human (clinically relevant) studies of any study design (at least 10 patients per study); English papers; and the following combination of key words within the title and/or abstract: "aldosterone" AND "bone", "skeleton", "osteoporosis", "fracture", "calcium", "parathyroid", "DXA", "osteocalcin", "P1NP", "alkaline phosphatase", "bone marker", "trabecular bone score", or "FRAX". The exclusion criteria were in vitro or animal studies, reviews, and case reports/series. We screened 1027 articles and finally included 23 studies (13 of case-control type, 3 cross-sectional, 5 prospective, 1 observational cohort, and 1 retrospective study). The assessments provided in these studies were as follows: nine studies addressed Dual-Energy X-ray Absorptiometry (DXA), another study pointed out a bone microarchitecture evaluation underlying trabecular bone score (TBS), and seven studies investigated the bone turnover markers (BTMs) profile. Moreover, 14 studies followed the subjects after adrenalectomy versus medical treatment, and 21 studies addressed secondary hyperparathyroidism in PA patients. According to our study on published data during a period of almost 40 years (n = 23, N = 3965 subjects aged between 38 and 64, with a mean age 56.75, and a female-to-male ratio of 1.05), a higher PTH in PA versus controls (healthy persons or subjects with essential hypertension) is expected, secondary hyperparathyroidism being associated in almost half of the adults diagnosed with PA. Additionally, mineral metabolism anomalies in PA may include lower serum calcium and higher urinary calcium output, all these three parameters being reversible under specific therapy for PA, regardless medical or surgical. The PA subgroup with high PTH seems at higher cardiovascular risk, while unilateral rather than bilateral disease was prone to this PTH anomaly. Moreover, bone mineral density (BMD) according to central DXA might show a higher fracture risk only in certain adults, TBS being a promising alternative (with a still unknown perspective of diabetes' influence on DXA-TBS results in PA). However, an overall increased fracture prevalence in PA is described in most studies, especially with respect to the vertebral site, the fracture risk that seems correctable upon aldosterone excess remission. These data recommend PA as a cause of secondary osteoporosis, a treatable one via PA intervention. There is still an area of debate the way to address BMTs profile in PA, the case's selection toward specific bone evaluation in every day practice, and further on, the understanding of the potential genetic influence at the level of bone and mineral complications in PA patients.

Multidisciplinary approach to sarcopenia: a narrative review

Sarcopenia is a condition in which muscle mass and strength are decreased and muscle function is impaired. It is an indicator of frailty and loss of independence in older adults. It is also associated with increased physical disability, which increases the risk of falls. As a multifactorial disease, sarcopenia is caused by a combination of factors including aging, hormonal changes, nutritional deficiencies, and physical inactivity. Understanding the underlying pathophysiology of sarcopenia and identifying its different causes is critical to developing effective prevention and treatment strategies. This review summarizes the pathophysiology, consequences, diagnostic methods, and multidisciplinary approaches to sarcopenia.

Ginsenoside Rc, an Active Component of Panax ginseng, Alleviates Oxidative Stress-Induced Muscle Atrophy via Improvement of Mitochondrial Biogenesis

Loss of skeletal muscle mass and function has detrimental effects on quality of life, morbidity, and mortality, and is particularly relevant in aging societies. The enhancement of mitochondrial function has shown promise in promoting muscle differentiation and function. Ginsenoside Rc (gRc), a major component of ginseng, has various pharmacological activities; however, its effect on muscle loss remains poorly explored. In this study, we examined the effects of gRc on the hydrogen peroxide (H2O2)-induced reduction of cell viability in C2C12 myoblasts and myotubes and H2O2-induced myotube degradation. In addition, we investigated the effects of gRc on the production of intracellular reactive oxygen species (ROS) and mitochondrial superoxide, ATP generation, and peroxisome proliferator-activated receptor-gamma co-activator 1α (PGC-1α) activity in myoblasts and myotubes under H2O2 treatment. Furthermore, to elucidate the mechanism of action of gRc, we conducted a transcriptome analysis of myotubes treated with or without gRc under H2O2 treatment. gRc effectively suppressed H2O2-induced cytotoxicity, intracellular ROS, and mitochondrial superoxide production, restored PGC-1α promoter activity, and increased ATP synthesis. Moreover, gRc significantly affected the expression levels of genes involved in maintaining mitochondrial mass and biogenesis, while downregulating genes associated with muscle degradation in C2C12 myotubes under oxidative stress. We provide compelling evidence supporting the potential of gRc as a promising treatment for muscle loss and weakness. Further investigations of the pharmacological effects of gRc under various pathological conditions of muscle loss will contribute to the clinical development of gRc as a therapeutic intervention.

Apoptosis and Autophagy, Different Modes of Cell Death: How to Utilize Them to Fight Diseases?

A careful balance between cell death and survival is of key importance when it comes to the maintenance of cellular homeostasis [...].