Effect of allopurinol on phosphocreatine recovery and muscle function in older people with impaired physical function: a randomised controlled trial

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.

The Current Landscape of Pharmacotherapies for Sarcopenia

Sarcopenia is a skeletal muscle disorder characterized by progressive and generalized decline in muscle mass and function. Although it is mostly known as an age-related disorder, it can also occur secondary to systemic diseases such as malignancy or organ failure. It has demonstrated a significant relationship with adverse outcomes, e.g., falls, disabilities, and even mortality. Several breakthroughs have been made to find a pharmaceutical therapy for sarcopenia over the years, and some have come up with promising findings. Yet still no drug has been approved for its treatment. The key factor that makes finding an effective pharmacotherapy so challenging is the general paradigm of standalone/single diseases, traditionally adopted in medicine. Today, it is well known that sarcopenia is a complex disorder caused by multiple factors, e.g., imbalance in protein turnover, satellite cell and mitochondrial dysfunction, hormonal changes, low-grade inflammation, senescence, anorexia of aging, and behavioral factors such as low physical activity. Therefore, pharmaceuticals, either alone or combined, that exhibit multiple actions on these factors simultaneously will likely be the drug of choice to manage sarcopenia. Among various drug options explored throughout the years, testosterone still has the most cumulated evidence regarding its effects on muscle health and its safety. A mas receptor agonist, BIO101, stands out as a recent promising pharmaceutical. In addition to the conventional strategies (i.e., nutritional support and physical exercise), therapeutics with multiple targets of action or combination of multiple therapeutics with different targets/modes of action appear to promise greater benefit for the prevention and treatment of sarcopenia.

Efficacy of Allopurinol in Improving Endothelial Dysfunction: A Systematic Review and Meta-Analysis

INTRODUCTION

Endothelial dysfunction has been implicated in various cardiovascular disorders as the initial pathology. Allopurinol has been shown to improve endothelial dysfunction in patients with gout, but its effect on cardiovascular patients is unclear.

AIMS

We aim to assess allopurinol efficacy in improving endothelial dysfunction overall and in different disease states including but not limited to heart failure, chronic kidney disease, ischemic heart disease METHODS: We conducted a literature search of PubMed, Cochrane's Central Library, and Scopus until December 2022, including randomized controlled trials and double-arm observational studies. The primary outcome measure was endothelial function assessed by change in flow mediated dilation (FMD) RESULTS: Our meta-analysis included 22 studies with a total of 1472 patients. Our pooled analysis shows that allopurinol significantly improved FMD (WMD = 1.46%, 95% CI [0.70, 2.22], p < 0.01) compared to control. However, there was no significant difference between allopurinol and control for endothelial-independent vasodilation measured by forearm blood flow (WMD = 0.10%, 95% CI [- 0.89, 0.69], p = 0.80). Subgroup analysis indicated that the effect of allopurinol on FMD was more significant in diabetic and congestive heart failure patients.

CONCLUSION

While allopurinol may improve endothelial function in various patient populations, further high-quality randomized controlled trials are needed to determine its efficacy in preventing cardiovascular disease exacerbation.

The association of allopurinol with persistent physical disability and frailty in a large community based older cohort

BACKGROUND

The protective effects of allopurinol on physical function in older adults are not well understood, despite its potential to improve functional gains and reduce sarcopenia. This study aims to determine the association between allopurinol, persistent physical disability, and frailty in older gout patients.

METHODS

This analysis used data from a randomized trial in an older cohort, ASPirin in Reducing Events in the Elderly (ASPREE). ASPREE recruited 19,114 participants aged ≥65 years without prior cardiovascular events, dementia, or independence-limiting physical disability at trial enrolment. This analysis examined the association of baseline and time-varying allopurinol use with persistent physical disability and new-onset frailty in participants with gout at baseline (self-report or use of any anti-gout medications). Frailty was measured using the Fried frailty phenotype (score ≥3/5) and a deficit accumulation frailty index (FI) (score >0.21/1.0). Multivariable Cox proportional-hazards models were used for main analyses.

RESULTS

This analysis included 1155 gout participants, with 630 taking allopurinol at baseline and 525 not. During a median follow-up of 5.7 years, 113 new allopurinol users were identified. Compared with nonusers, baseline allopurinol use was associated with a significant risk reduction of persistent physical disability (Adjusted HR 0.46, 95% CI 0.23-0.92, p = 0.03). The strength of the association was modestly attenuated in the time-varying analysis (Adjusted HR 0.56, 0.29-1.08, p = 0.08). No significant associations with frailty measures were observed for either baseline allopurinol use (Fried frailty: Adjusted HR 0.83, 0.62-1.12; FI: Adjusted HR 0.96, 0.74-1.24) or time-varying allopurinol use (Fried frailty: Adjusted HR 0.92, 0.69-1.24; FI: Adjusted HR 1.02, 0.78-1.33).

CONCLUSIONS

Allopurinol use in older adults with gout is associated with a reduced risk of persistent physical disability but not associated with risk of frailty.

The Effectiveness of L-arginine in Clinical Conditions Associated with Hypoxia

The review summarises the data of the last 50 years on the effectiveness of the amino acid L-arginine in therapeutic practice in conditions accompanied by different-origin hypoxia. The aim of this review was to analyse the literature and our research data on the role of nitric oxide in the modulation of individual physiological reactivity to hypoxia. The review considers the possibility of eliminating methodological conflicts in the case of L-arginine, which can be solved by taking into account individual physiological reactivity (or the hypoxia resistance factor). Considerable attention is paid to genetic and epigenetic mechanisms of adaptation to hypoxia and conditions of adaptation in different models. The article presents data on the clinical effectiveness of L-arginine in cardiovascular system diseases (hypertension, atherosclerosis, coronary heart disease, etc.) and stress disorders associated with these diseases. The review presents a generalised analysis of techniques, data on L-arginine use by athletes, and the ambiguous role of NO in the physiology and pathology of hypoxic states shown via nitric oxide synthesis. Data on the protective effects of adaptation in the formation of individual high reactivity in sportsmen are demonstrated. The review demonstrates a favourable effect of supplementation with L-arginine and its application depending on mitochondrial oxidative phosphorylation processes and biochemical indices in groups of individuals with low and high capacity of adaptation to hypoxia. In individuals with high initial anti-hypoxic reserves, these favourable effects are achieved by the blockade of NO-dependent biosynthesis pathways. Therefore, the methodological tasks of physiological experiments and the therapeutic consequences of treatment should include a component depending on the basic level of physiological reactivity.