This study evaluated the association between nutritional status, depressive symptoms, and the number of prescription drugs taken by older adults living in nursing homes in Mexico City. In a cross-sectional study, 262 participants were subjected to anthropometric and nutritional (Mini Nutritional Assessment (MNA)) evaluations; additionally, their depression (Geriatric Depression Scale (GDS)) and functional status were assessed. Multiple logistic regression was used for identifying factors associated with the risk of malnutrition/malnourishment. The mean age of participants was 83.1 ± 8.6 years. A total of 59.9% and 21.1% were at risk of malnutrition and malnourished, respectively. With respect to depression, 27.9% of the participants had mild depression, while 11.4% showed severe depression. An inverse correlation between MNA evaluations and depression scores was found (Spearman’s ρ = −0.4624, p < 0.001); residents with a better nutritional status had lower depression scores. Individuals with depressive symptoms were approximately five times more likely to be at risk of malnutrition or malnourished (OR = 5.82, 95% CI = 2.27–14.89) than individuals without depression. Residents taking three or more prescription drugs daily (OR = 1.83, 95% CI = 1.27–2.63, p < 0.001) were more likely to be at risk of malnutrition or malnourished. In summary, poor nutritional status was associated with depression, while the intake of numerous prescription drugs was associated with being at risk of malnutrition or malnourished.

Aging reduces homeostasis and contributes to increasing the risk of brain diseases and death. Some of the principal characteristics are chronic and low-grade inflammation, a general increase in the secretion of proinflammatory cytokines, and inflammatory markers. Aging-related diseases include focal ischemic stroke and neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). Flavonoids are the most common class of polyphenols and are abundantly found in plant-based foods and beverages. A small group of individual flavonoid molecules (e.g., quercetin, epigallocatechin-3-gallate, and myricetin) has been used to explore the anti-inflammatory effect in vitro studies and in animal models of focal ischemic stroke and AD and PD, and the results show that these molecules reduce the activated neuroglia and several proinflammatory cytokines, and also, inactivate inflammation and inflammasome-related transcription factors. However, the evidence from human studies has been limited. In this review article, we highlight the evidence that individual natural molecules can modulate neuroinflammation in diverse studies from in vitro to animal models to clinical studies of focal ischemic stroke and AD and PD, and we discuss future areas of research that can help researchers to develop new therapeutic agents.

Leucine has been shown to acutely inhibit hepatic glucose production in rodents by a mechanism requiring its metabolism to acetyl-CoA in the mediobasal hypothalamus (MBH). In the early stages, all branched-chain amino acids (BCAA) are metabolized by a shared set of enzymes to produce a ketoacid, which is later metabolized to acetyl-CoA. Consequently, isoleucine and valine may also modulate glucose metabolism. To examine this possibility we performed intrahypothalamic infusions of isoleucine or valine in rats and assessed whole body glucose kinetics under basal conditions and during euglycemic pancreatic clamps. Furthermore, because high fat diet (HFD) consumption is known to interfere with central glucoregulation, we also asked whether the action of BCAAs was affected by HFD. We fed rats a lard-rich diet for a short interval and examined their response to central leucine. The results showed that both isoleucine and valine individually lowered blood glucose by decreasing liver glucose production. Furthermore, the action of the BCAA leucine was markedly attenuated by HFD feeding. We conclude that all three BCAAs centrally modulate glucose metabolism in the liver and that their action is disrupted by HFD-induced insulin resistance.

Zinc (Zn) is an essential trace element; it exhibits a plethora of physiological properties and biochemical functions. It plays a pivotal role in regulating the cell cycle, apoptosis, and DNA organization, as well as in protein, lipid, and carbohydrate metabolism. Among other important processes, Zn plays an essential role in reproductive health. The ZIP and ZnT proteins are responsible for the mobilization of Zn within the cell. Zn is an inert antioxidant through its interaction with a variety of proteins and enzymes to regulate the redox system, including metallothioneins (MTs), metalloenzymes, and gene regulatory proteins. The role of Zn in the reproductive system is of great importance; processes, such as spermatogenesis and sperm maturation that occur in the testicle and epididymis, respectively, depend on this element for their development and function. Zn modulates the synthesis of androgens, such as testosterone, for these reproductive processes, so Zn deficiency is related to alterations in sperm parameters that lead to male infertility.

The aim of this study was to evaluate the association between handgrip strength, nutritional status and vitamin D deficiency in Mexican community-dwelling older women. A cross sectional study in women ≥ 60 years-old was performed. Plasma 25-hydroxyvitamin D (25(OH)D) concentrations were measured by a quantitative immunoassay technique. Handgrip strength was assessed using a dynamometer, while nutritional status was assessed through the Full Mini Nutritional Assessment (Full-MNA). A total of 116 women participated in the study, their mean age was 70.3 ± 5.8 years; 49.1% of the study group had plasma 25(OH)D levels lower than 40 nmol/L [16 ng/mL]. Meanwhile, 28.45% of participants had low handgrip strength (<16 kg), and 23.1% were identified at risk of malnutrition/malnourished according with Full-MNA score. Women with 25(OH)D deficiency (<40 nmol/L [16 ng/mL]) were more likely to have low handgrip strength (OR = 2.64, p = 0.025) compared with those with higher 25(OH)D values. Additionally, being malnourished or at risk of malnutrition (OR = 2.53, p = 0.045) or having type 2 diabetes mellitus (T2DM) (OR = 2.92, p = 0.044) was also associated with low 25(OH)D. The prevalence of low plasma 25(OH)D concentrations was high among Mexican active older women. Low handgrip strength, being at risk of malnutrition/malnourished, or diagnosed with T2DM was also associated with Vitamin D deficiency.

Diabetes is a metabolic disease with a high worldwide prevalence and an important factor in mortality and disability in the population. Complications can be reduced or prevented with lifestyle changes in physical activity, dietary habits, and smoking cessation. High-protein diets (HPDs, >30% or >1.0 g/Kg/day) decrease hyperglycemia in part due to their content of branched-chain amino acids (BCAAs), mainly leucine. Leucine (and other BCAAs) improve glucose metabolism by directly signaling in the medio-basal hypothalamus (MBH), increasing liver insulin sensitivity. To determine the effectiveness of an HPD to lower hyperglycemia, we analyzed the results of published clinical studies focusing on the levels of fasting plasma glucose and/or glycosylated hemoglobin (HbA1c) in patients with type 2 diabetes mellitus (T2DM). We carried out a systematic search for clinical studies using HPDs. We searched five databases (Scopus, Web of Science, PubMed, Epistemonikos, and Cochrane), collecting 179 articles and finally selecting 8 articles to analyze their results. In conclusion, HPDs are an effective alternative to reduce hyperglycemia in patients with T2DM, especially so-called Paleolithic diets, due to their higher-quality protein from animal and vegetal sources and their exclusion of grains, dairy products, salt, refined fats, and added sugars.