Physical exercise (PE) improves physical performance, mental status, general health, and well-being. It does so by affecting many mechanisms at the cellular and molecular level. PE is beneficial for people suffering from neuro-degenerative diseases because it improves the production of neurotrophic factors, neurotransmitters, and hormones. PE promotes neuronal survival and neuroplasticity and also optimizes neuroendocrine and physiological responses to psychosocial and physical stress. PE sensitizes the parasympathetic nervous system (PNS), Autonomic Nervous System (ANS) and central nervous system (CNS) by promoting many processes such as synaptic plasticity, neurogenesis, angiogenesis, and autophagy. Overall, it carries out many protective and preventive activities such as improvements in memory, cognition, sleep and mood; growth of new blood vessels in nervous system; and the reduction of stress, anxiety, neuro-inflammation, and insulin resistance. In the present work, the protective effects of PE were overviewed. Suitable examples from the current research work in this context are also given in the article.

The steady rise in antimicrobial resistance poses a severe threat to global public health by hindering treatment of an escalating spectrum of infections. We have previously established the potent activity of α-MSH, a 13 residue antimicrobial peptide, against the opportunistic pathogen Staphylococcus aureus. Here, we sought to determine whether an increase in cationic charge in α-MSH could contribute towards improving its staphylocidal potential by increasing its interaction with anionic bacterial membranes. For this we designed novel α-MSH analogues by replacing polar uncharged residues with lysine and alanine. Similar to α-MSH, the designed peptides preserved turn/random coil conformation in artificial bacterial mimic 1,2-dimyristoyl-sn-glycero-3-phosphocholine:1,2-dimyristoyl-sn-glycero-3-phospho-rac-(1-glycerol) (7:3, w/w) vesicles and showed preferential insertion in the hydrophobic core of anionic membranes. Increased cationic charge resulted in considerable augmentation of antibacterial potency against MSSA and MRSA. With ~18-fold better binding than α-MSH to bacterial mimic vesicles, the most charged peptide KKK-MSH showed enhanced membrane permeabilization and depolarization activity against intact S. aureus. Scanning electron microscopy confirmed a membrane disruptive mode of action for KKK-MSH. Overall, increasing the cationic charge improved the staphylocidal activity of α-MSH without compromising its cell selectivity. The present study would help in designing more effective α-MSH-based peptides to combat clinically relevant staphylococcal infections.

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Cancer cells exhibit various degrees of mitochondrial metabolic alterations. Owing to their multiple roles, mitochondria are attractive target for cancer therapy. Cancerous cells have high glucose (HG) requirements for their growth. Depriving them of glucose has been an approach used in many studies to restrict their perpetuation. However, such deprivation can negatively affect the surrounding normal cells in vivo. Keeping this in view, we treated HeLa cells with only physiological glucose (PG, 5.5 mM) and a combination of physiological glucose with a very low dose (1 nM) of rotenone (PGT), taking high glucose (HG, 25 mM)-treated HeLa cells as normal. We demonstrated that HeLa cells under PG condition mainly exhibited growth arrest. The PGT combination induced apoptosis in HeLa cells by generation of ROS, decrease in ATP production even with around 1.89-fold increase in glucose consumption, cell cycle arrest at S-phase and substantial increase in sub-diploid (Sub-D) population. The oxidative stress generated in both PG and PGT conditions stabilised p53 by localising it in the nuclei of HeLa cells, which would have otherwise undergone HPV-mediated inactivation. Pre-mature senescence induced due to limited glucose availability was found to be regulated by nuclear translocated p53 which, in turn, induced p21, pAkt and pERK. The cyto-toxic effect of rotenone on glucose deprived HeLa cells, synergistically activated NFκB, caspase-3 and Bax along with reduced expression of hyaluronan, a ROS scavenging molecule on their cell surface. Thus, our finding might be a valuable approach to specifically target cancerous cells in a more physiologically feasible condition and can serve as a relevant biochemical basis to gain new insights into cancer therapy.

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