Traumatic brain injury has long-term detrimental effects on neurological function and general quality of life of affected individuals. Bioenergetic failure is a primary mechanism for cellular dysfunction. We used the mitochondrial activator humanin (HN) to try to normalize the disruptive action of TBI on cellular bioenergetics in the hippocampus. We found that HN supplied right after the injury counteracted the action of TBI on metabolic sensing proteins (LKB1, AMPK, and AKT). HN also counteracted cognitive function and restored the synaptic proteins (Synapsin I and PSD-95) at three weeks post-injury. Moreover, HN normalized the disruptive action of TBI on mitochondrial functioning and dynamics (fusion, fission, and mitophagy). In addition, HN treatment counteracted TBI’s effects on mitochondrial biogenesis (PGC-1α), antioxidant (SOD2), and apoptotic marker (CC3). Furthermore, HN intervention in injured animals counteracted the gene expression linked with inflammation (Itgax, SALL1, GFAP, and NLRP3), synaptic plasticity (HDAC2), and bioenergetics (mtND2, TFAM, SIRT1, and SIRT3). These observations emphasize the therapeutic potential of HN by normalizing the fundamental aspects of TBI pathogenesis central to cellular bioenergetics and synaptic plasticity.
β‐amyloid (Aβ) peptide is a hallmark of Alzheimer’s disease (AD) and associated with a progressive decline of cognition, a characteristic feature of AD. Aggregation of Aβ initiates the dysregulation of calcium ion homeostasis. Recently, it has been shown that transient receptor potential melastatin 2 (TRPM2), a Ca 2+ ‐permeable non‐selective cation channel plays a crucial role in the Aβ‐induced neuronal cell death. However, the therapeutic potential of 2‐aminoethoxydiphenyl borate (2‐APB), a TRPM2 inhibitor has not been investigated in the Aβ‐induced cognitive deficits in rats yet. In the present study, I.C.V. administration of Aβ (Aβ 25‐35, 10 μg) markedly induced cognitive impairment which shown in cognitive behavioral parameters. Moreover, mRNA and protein expression of TRPM2 were upregulated in the hippocampus of Aβ‐treated animals. AchE activity was also increased in the cortex of Aβ‐treated animals. Three‐week treatment with 2‐APB led to the down‐regulation of TRPM2 mRNA and protein expression in the hippocampus and also improved the cognitive functions. Moreover, the 2‐APB treatment also increased the calcium and memory associated proteins namely p‐CaMKII, p‐GSK3β, p‐CREB and PSD‐95 in the hippocampus and reduced the mRNA level of calcium buffering protein and calcineurin A (PPP3CA) in the hippocampus. Furthermore, 2‐APB significantly reduced the AchE activity in the cortex. Thus, our findings suggest that 2‐APB depicted potential neuroprotective effect against Aβ‐induced cognitive impairment. Support or Funding Information: National Institute of Pharmaceutical Education and Research and National Agri‐Food Biotechnology Institute
Traumatic brain injury (TBI) and non-acquired brain damage represent a catastrophic global health burden, frequently resulting in persistent neurological impairment, long-term cognitive decline, and increased susceptibility to secondary psychiatric disorders