Combinatorial therapy of exercise-preconditioning and nanocurcumin formulation supplementation improves cardiac adaptation under hypobaric hypoxia

Current study on Pyrroloquinoline quinone (PQQ) therapeutic role in neurodegenerative diseases

Pyrroloquinoline quinone (PQQ) is a naturally occurring redox-active compound with potent antioxidant, mitochondrial-enhancing, and neuroprotective properties. Originally identified as a cofactor in bacterial enzymes, PQQ has garnered significant interest for its potential therapeutic role in neurodegenerative diseases, including Alzheimer's disease (AD) and Parkinson's disease (PD). It has reported that PQQ exerts its effects through several key molecular mechanisms, including the activation of antioxidant pathways via Nrf2/ARE signaling, enhancement of mitochondrial biogenesis and function through AMPK/PGC-1α, and the regulation of inflammatory processes through NF-κB inhibition. By improving cellular energy metabolism, reducing oxidative stress, and promoting neuronal survival, PQQ offers a multifaceted approach to counteracting the pathophysiological factors underlying neurodegeneration. Our review focusing on current study of PQQ on its enhancing neuroplasticity, and protecting neurons from damage induced by oxidative stress, mitochondrial dysfunction, and inflammation. Further we reviewed the significant signaling pathways that involved PQQ neuroprotective mechanisms, positioning it as a novel candidate for future therapeutic strategies targeting these debilitating conditions.

Effect of hypobaric hypoxia on the fiber type transition of skeletal muscle: a synergistic therapy of exercise preconditioning with a nanocurcumin formulation

Hypobaric hypoxia (HH) leads to various adverse effects on skeletal muscles, including atrophy and reduced oxidative work capacity. However, the effects of HH on muscle fatigue resistance and myofiber remodeling are largely unexplored. Therefore, the present study aimed to explore the impact of HH on slow-oxidative fibers and to evaluate the ameliorative potential of exercise preconditioning and nanocurcumin formulation on muscle anti-fatigue ability. C2C12 cells (murine myoblasts) were used to assess the effect of hypoxia (0.5%, 24 h) with and without the nanocurcumin formulation (NCF) on myofiber phenotypic conversion. To further validate this hypothesis, male Sprague Dawley rats were exposed to a simulated HH (7620 m) for 7 days, along with NCF administration and/or exercise training. Both in vitro and in vivo studies revealed a significant reduction in slow-oxidative fibers (p < 0.01, 61% vs. normoxia control) under hypoxia. There was also a marked decrease in exhaustion time (p < 0.01, 65% vs. normoxia) in hypoxia control rats, indicating a reduced work capacity. Exercise preconditioning along with NCF supplementation significantly increased the slow-oxidative fiber proportion and exhaustion time while maintaining mitochondrial homeostasis. These findings suggest that HH leads to an increased transition of slow-oxidative fibers to fast glycolytic fibers and increased muscular fatigue. Administration of NCF in combination with exercise preconditioning restored this myofiber remodeling and improved muscle anti-fatigue ability.

A Nanocurcumin and Pyrroloquinoline Quinone Formulation Prevents Hypobaric Hypoxia-Induced Skeletal Muscle Atrophy by Modulating NF-κB Signaling Pathway

Kushwaha, Asha D., and Deepika Saraswat. A nanocurcumin and pyrroloquinoline quinone formulation prevents hypobaric hypoxia-induced skeletal muscle atrophy by modulating NF-κB signaling pathway. High Alt Med Biol 00:000-000, 2022. Background: Hypobaric hypoxia (HH)-induced deleterious skeletal muscle damage depends on exposure time and availability of oxygen at cellular level, which eventually can limit human work performance at high altitude (HA). Despite the advancements made in pharmacological (performance enhancer, antioxidants) and nonpharmacological therapeutics (acclimatization strategies), only partial success has been achieved in improving physical performance at HA. A distinctive combination of nanocurcumin (NC) and pyrroloquinoline quinone (PQQ) has been formulated (named NCF [nanocurcumin formulation], Indian patent No. 302877) in our laboratory, and has proven very promising in improving cardiomyocyte adaptation to chronic HH. We hypothesized that NCF might improve skeletal muscle adaptation and could be a performance enhancer at HA. Material and Methods: Adult Sprague-Dawley rats (220 ± 10 g) were divided into five groups (n = 6/group): normoxia vehicle control, hypoxia vehicle control, hypoxia NCF, hypoxia NC, and hypoxia PQQ. All the animals (except those in normoxia) were exposed to simulated HH in a chamber at temperature 22°C ± 2°C, humidity 50% ± 5%, altitude 25,000 ft for 1, 3, or 7 days. After completion of the stipulated exposure time, gastrocnemius and soleus muscles were excised from animals for further analysis. Results: Greater lengths of hypoxic exposure caused progressively increased muscle ring finger-1 (MuRF-1; p < 0.01) expression and calpain activation (0.56 ± 0.05 vs. 0.13 ± 0.02 and 0.44 ± 0.03 vs. 0.12 ± 0.021) by day 7, respectively in the gastrocnemius and soleus muscles. Myosin heavy chain type I (slow oxidative) fibers significantly (p > 0.01) decreased in gastrocnemius (>50%) and soleus (>46%) muscles by the seventh day of exposure. NCF supplementation showed (p ≤ 0.05) tremendous improvement in skeletal muscle acclimatization through effective alleviation of oxidative damage, and changes in calpain activity and atrophic markers at HA compared with hypoxia control or treatment alone with NC/PQQ. Conclusion: Thus, NCF-mediated anti-oxidative, anti-inflammatory effects lead to decreased proteolysis resulting in mitigated skeletal muscle atrophy under HH.

Nanocurcumin formulation: a possible therapeutic agent for post COVID inflammatory syndrome

Over the last twenty months, the attention of the world has been focusing on managing the unprecedented and devastating wave of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV 2) and mitigating its impacts. Recent findings indicated that high levels of pro-inflammatory cytokines are leading cause of poor prognosis in severely ill COVID-19 patients. Presently, the multiple variants and highly contagious nature of virus makes challenge humongous. The shortage and vaccine hesitancy also prompted to develop antiviral therapeutic agents to manage this pandemic. Nanocurcumin has potential antiviral activities and also beneficial in post COVID inflammatory complications. We have developed nanocurcumin based formulation using pyrroloquinoline quinone (PQQ) which protects cardio-pulmonary function and mitochondrial homeostasis in hypobaric hypoxia induced right ventricular hypertrophy in animal model and human ventricular cardiomyocytes. Nanocurcumin based formulation (NCF) with improved bioavailability, has proven several holistic therapeutic effects including myocardial protection, and prevents edema formation, anti-inflammatory and antioxidant properties, maintaining metabolic and mitochondrial homeostasis under hypoxic condition. The post COVID-inflammatory syndrome also reported to cause impaired heart function, lung injuries and increased C-reactive protein level in severely ill patients. Thus, we speculate that NCF could be a new treatment option to manage post COVID-19 inflammatory syndrome.

Oxidative Stress, Kinase Activity and Inflammatory Implications in Right Ventricular Hypertrophy and Heart Failure under Hypobaric Hypoxia

High altitude (hypobaric hypoxia) triggers several mechanisms to compensate for the decrease in oxygen bioavailability. One of them is pulmonary artery vasoconstriction and its subsequent pulmonary arterial remodeling. These changes can lead to pulmonary hypertension and the development of right ventricular hypertrophy (RVH), right heart failure (RHF) and, ultimately to death. The aim of this review is to describe the most recent molecular pathways involved in the above conditions under this type of hypobaric hypoxia, including oxidative stress, inflammation, protein kinases activation and fibrosis, and the current therapeutic approaches for these conditions. This review also includes the current knowledge of long-term chronic intermittent hypobaric hypoxia. Furthermore, this review highlights the signaling pathways related to oxidative stress (Nox-derived O₂^.- and H₂O₂), protein kinase (ERK5, p38α and PKCα) activation, inflammatory molecules (IL-1β, IL-6, TNF-α and NF-kB) and hypoxia condition (HIF-1α). On the other hand, recent therapeutic approaches have focused on abolishing hypoxia-induced RVH and RHF via attenuation of oxidative stress and inflammatory (IL-1β, MCP-1, SDF-1 and CXCR-4) pathways through phytotherapy and pharmacological trials. Nevertheless, further studies are necessary.

Pyrroloquinoline quinone attenuates isoproterenol hydrochloride‑induced cardiac hypertrophy in AC16 cells by inhibiting the NF‑κB signaling pathway

Pyrroloquinoline quinone (PQQ) is a naturally occurring redox co-factor that functions as an essential nutrient and antioxidant, and has been reported to exert potent anti-inflammatory effects. However, the therapeutic potential of PQQ for isoproterenol hydrochloride (Iso)-induced cardiac hypertrophy has not yet been explored, at least to the best of our knowledge. In the present study, the anti-inflammatory effects of PQQ were investigated in Iso-treated AC16 cells, a myocardial injury cellular model characterized by an increase in the apparent surface area of the cells and the activation of intracellular cardiac hypertrophy-associated proteins. The results revealed that pre-treatment with PQQ significantly inhibited the expression of cardiac hypertrophy marker proteins, such as atrial natriuretic peptide, brain natriuretic peptide and β-myosin heavy chain. PQQ also inhibited the activation of the nuclear factor (NF)-κB signaling pathway in Iso-treated AC16 cells, thus inhibiting the nuclear translocation of NF-κB and reducing the phosphorylation levels of p65. On the whole, the findings of this study suggest that PQQ may be a promising therapeutic agent for effectively reversing the progression of cardiac hypertrophy.

Aerobic exercise promotes the expression of ERCC1 to prolong lifespan: A new possible mechanism

Aerobic exercise can delay aging and extend lifespan, but its specific mechanism still remains unclear. One popular theory is that with age and the cell division times increasing, DNA damage will inevitably accumulate, leading to dysfunction and failure of various tissues and organs, which will eventually lead to aging. Thus, repairing damaged DNA is a key strategy to extend lifespan. Excision repair cross-complementary gene 1 (ERCC1) is a DNA repair enzyme that recognizes, excises and repairs damaged DNA. Defects or reduced activity of the enzyme can lead to DNA damage accumulation. This study provides that aerobic exercise can significantly extend rats' lifespan and increase the expression of ERCC1 in heart, brain, liver and kidney. Therefore, based on our experiments, we propose the following scientific hypothesis: aerobic exercise can up-regulate the expression of ERCC1 and then may reduce DNA damage accumulation to maintain genomic integrity and stability, thereby delaying aging and prolonging lifespan in humans.