Chronic caloric restriction triggers unfavorable alterations in cardiac function albeit responsible scenarios remain unclear. This work evaluated the possible involvement of Akt2 in caloric restriction-evoked cardiac geometric and functional changes and responsible processes focusing on autophagy and mitophagy. Akt2 knockout and WT mice were subjected to caloric restriction for 30 weeks prior to assessment of myocardial homeostasis. Caloric restriction compromised echocardiographic parameters (decreased LV wall thickness, LVEDD, stroke volume, cardiac output, ejection fraction, fractional shortening, and LV mass), cardiomyocyte contractile and intracellular Ca2+ capacity, myocardial atrophy, interstitial fibrosis and mitochondrial injury associated with elevated blood glucocorticoids, autophagy (LC3B, p62, Atg7, Beclin-1), and mitophagy (Pink1, Parkin, TOM20), dampened cardiac ATP levels, mitochondrial protein PGC1α and UCP2, anti-apoptotic protein Bcl2, intracellular Ca2+ governing components Na+-Ca2+ exchanger, phosphorylation of SERCA2a, mTOR (Ser2481) and ULK1 (Ser757), and upregulated Bax, phospholamban, phosphorylation of Akt2, AMPK, and ULK1 (Ser555), the responses except autophagy markers (Beclin-1, Atg7), phosphorylation of AMPK, mTOR and ULK1 were negated by Akt2 ablation. Levels of CDK1 and DRP1 phosphorylation were overtly upregulated with caloric restriction, the response was reversed by Akt2 knockout. Caloric restriction-evoked changes in cardiac remodeling and cardiomyocyte function were alleviated by glucocorticoid receptor antagonism, Parkin ablation and Mdivi-1. In vitro experiment indicated that serum deprivation or glucocorticoids evoked GFP-LC3B accumulation and cardiomyocyte dysfunction, which was negated by inhibition of Akt2, CDK1 or DRP1, whereas mitophagy induction reversed Akt2 ablation-evoked cardioprotection. These observations favor a protective role of Akt2 ablation in sustained caloric restriction-evoked cardiac pathological changes via correction of glucocorticoid-induced mitophagy defect in a CDK1-DRP1-dependent manner.

BACKGROUND: Oral cancer poses a significant threat to public health worldwide. In addition, because many chemotherapy treatments have negative side effects, natural herbs may be beneficial for oral cancer therapy. Achyranthes aspera (AA), a potential medicinal herb, exerts various pharmacological and biochemical activities.
OBJECTIVE: The present study aimed to predict the anti-oral cancer potential of AA using in silico tools and cell death by in vitro testing.
METHODS: A total of fourteen bioactive constituents from AA herb were selected using phytochemical databases. The toxicity of AA herb extract was analysed through MTT assay against oral carcinoma A253 cell line. The binding activities of the phytocomponents against serine/ threonine-specific protein kinases isoforms, namely Akt1 (PDB ID: 3qkk) and Akt2 (PDB ID: 2jdo) proteins, were analysed using Discovery Studio 2021 and PyRx docking software.
RESULTS: Cell viability data revealed that AA extract decreased the viability and reduced the number of live cells of the oral carcinoma A253 cell line in a dose-dependent manner. The halfmaximal concentration (IC50) value of AA was assessed as 204.74 μg/ml. Based on binding affinity, saponin C (-CDOCKER energy = -77.9862), oleanolic acid (-CDOCKER energy = - 49.4349), spinasterol (-CDOCKER energy = -38.1246), 36,47-dihydroxyhenpentacontan-4-one (-CDOCKER energy = -32.4386), and 20-hydroxyecdysone (-CDOCKER energy = -31.9138) were identified as the best compounds against Akt1, while, compounds saponin C (-CDOCKER energy = -134.412), oleanolic acid (-CDOCKER energy = -90.0846), spinasterol (-CDOCKER energy = -78.3213), 20-hydroxyecdysone (-CDOCKER energy = -80.1049), and ecdysone (- CDOCKER energy = -73.3885) were identified as Akt2 inhibitors. These top compounds fulfilled drug score values, pharmacokinetic and physicochemical characteristics, and druglikeness parameters.
CONCLUSIONS: The present findings reveal that the lead phytomolecules of AA could be effective and developed as a prospective drug against oral cancer.

Infectious challenge can trigger alterations in sleep-wake behavior. Accumulating evidence has shown that the serine/threonine kinases Akt1 and Akt2 are important targets in both physiological and infectious signaling processes. However, the involvement of Akt1 and Akt2 in sleep-wake activity under basal conditions and in response to inflammatory stimulation has not been established. In the present study, we assessed the precise role of Akt1 and Akt2 in sleep-wake behavior using electroencephalography (EEG)/electromyography (EMG) data from Akt1- and Akt2-deficient mice and wild-type (WT) mice. The results showed that both Akt1 and Akt2 deficiency affect sleep-wake activity, as indicated by reduced nonrapid eye movement (NREM) sleep and increased wakefulness in mutant mice compared to WT mice. Sleep amount and intensity (delta, theta and alpha activity) at night were also drastically attenuated in Akt1- and Akt2-deficient mice. Moreover, since Akt1 and Akt2 are involved in immune responses, we assessed their roles in the sleep response to the inflammatory stimulus lipopolysaccharide (LPS) throughout the following 24 h. We observed that the decrease in wakefulness and increase in NREM sleep induced by LPS were restored in Akt1 knockout mice but not in Akt2 knockout mice. Correspondingly, the decrease in the number of positive orexin-A neurons induced by LPS was abrogated in Akt1 knockout mice but not in Akt2 knockout mice. Our results revealed that both Akt1 and Akt2 deficiency affect the sleep response under basal conditions, but only Akt1 deficiency protects against the aberrant changes in sleep behavior induced by peripheral immune challenge.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s41105-024-00519-y.

A better understanding of nicotine neurobiology is needed to reduce or prevent chronic addiction, ameliorate the detrimental effects of nicotine withdrawal, and increase successful cessation of use. Nicotine binds and activates two astrocyte-expressed nicotinic acetylcholine receptors (nAChRs), α4β2 and α7. We recently found that Protein kinase B-β (Pkb-β or Akt2) expression is restricted to astrocytes in mice and humans. To determine if AKT2 plays a role in astrocytic nicotinic responses, we generated astrocyte-specific Akt2 conditional knockout (cKO) and full Akt2 KO mice for in vivo and in vitro experiments. For in vivo studies, we examined mice exposed to chronic nicotine for two weeks in drinking water (200 μg/mL) and following acute nicotine challenge (0.09, 0.2 mg/kg) after 24 hrs. Our in vitro studies used cultured mouse astrocytes to measure nicotine-dependent astrocytic responses. We validated our approaches using lipopolysaccharide (LPS) exposure inducing astrogliosis. Sholl analysis was used to measure glial fibrillary acidic protein responses in astrocytes. Our data show that wild-type (WT) mice exhibit increased astrocyte morphological complexity during acute nicotine exposure, with decreasing complexity during chronic nicotine use, whereas Akt2 cKO mice showed increased astrocyte morphology complexity. In culture, we found that 100μM nicotine was sufficient for morphological changes and blocking α7 or α4β2 nAChRs prevented observed morphologic changes. Finally, we performed conditioned place preference (CPP) in Akt2 cKO mice and found that astrocytic AKT2 deficiency reduced nicotine preference compared to controls. These findings show the importance of nAChRs and Akt2 signaling in the astrocytic response to nicotine.

OBJECTIVE: High expression of phosphatidylinositol 4-kinase III alpha (PI4KIIIα) correlates with poor survival rates in patients with hepatocellular carcinoma. In addition, hepatitis C virus (HCV) infections activate PI4KIIIα and contribute to hepatocellular carcinoma progression. We aimed at mechanistically understanding the impact of PI4KIIIα on the progression of liver cancer and the potential contribution of HCV in this process.
METHODS: Several hepatic cell culture and mouse models were used to study the functional importance of PI4KIIIα on liver pathogenesis. Antibody arrays, gene silencing, and PI4KIIIα-specific inhibitor were applied to identify the involved signaling pathways. The contribution of HCV was examined by using HCV infection or overexpression of its nonstructural protein.
RESULTS: High PI4KIIIα expression and/or activity induced cytoskeletal rearrangements via increased phosphorylation of paxillin and cofilin. This led to morphologic alterations and higher migratory and invasive properties of liver cancer cells. We further identified the liver-specific lipid kinase phosphatidylinositol 3-kinase C2 domain-containing subunit gamma (PIK3C2γ) working downstream of PI4KIIIα in regulation of the cytoskeleton. PIK3C2γ generates plasma membrane phosphatidylinositol 3,4-bisphosphate-enriched, invadopodia-like structures that regulate cytoskeletal reorganization by promoting Akt2 phosphorylation.
CONCLUSIONS: PI4KIIIα regulates cytoskeleton organization via PIK3C2γ/Akt2/paxillin-cofilin to favor migration and invasion of liver cancer cells. These findings provide mechanistic insight into the contribution of PI4KIIIα and HCV to the progression of liver cancer and identify promising targets for therapeutic intervention.

AKT2 is crucial for cancer cells\' invasion, metastasis, and survival. It is a possible downstream gene target of cancer glycolysis-related microRNAs. The study investigated the role of miRNA-4716-3p, rs2304186, and the AKT2 gene in blood cancer pathogenesis. RT-qPCR was used to analyze AKT2 gene mRNA and miRNA-4716-3p expression in 200 blood cancer samples and 200 healthy controls. Furthermore, Tetra-ARMS PCR was used to examine the rs2304186 AKT2 SNP in 300 patients and 290 control samples. miRNA-4716-3p was shown to be significantly downregulated (p = 0.0294), whereas mRNA expression of the AKT2 gene was found to be significantly upregulated (p = 0.0034) in blood cancer patients compared to healthy individuals. miRNA-4716-3p downregulation (p = 0.0466) was more pronounced, while AKT2 upregulation was non-significant (p = 0.1661) in untreated patients compared to chemotherapy-treated patients. Blood cancer risk was significantly associated with the rs2304186 GT genotype (p = 0.0432), TT genotype (p = 0.0502), and mutant allele (T) frequency (p = 0.0008). Polymorphism rs2304186 was associated with an increased risk of blood cancer in dominant (p = 0.0011), recessive (p = 0.0502), and additive (p = 0.0008) genetic models. The results suggested that the rs2304186 and the deregulated expression of miRNA-4716-3p and AKT2 gene at the mRNA level may significantly increase the incidence of blood cancer, particularly in the Pakistani population. Therefore, these may function as suitable biomarkers for blood cancer diagnosis and prognosis. Additional, larger-scale investigations may be required to affirm these results.

UNASSIGNED: The gain-of-function AKT2 c.49G>A variant causes hypoketotic hypoglycemia with variable associated features. Due to lack of effective medications, treatment is primarily supportive. This report suggests waxy maize heat is a viable treatment option.
UNASSIGNED: The serine-threonine kinase AKT2 is a critical mediator of insulin\'s anabolic effects, particularly cellular glucose uptake. The gain-of-function c.49G>A, p.(Glu17Lys) AKT2 variant results in hypoketotic hypoglycemia with suppressed insulin and free fatty acid levels due to constitutive activation of the insulin signaling cascade. Although biochemical similarities exist among the eight individuals identified to date, the associated phenotype varies considerably. Treatment of these patients remains challenging, consisting primarily of frequent feeds with uncooked cornstarch. We describe a female with hemihypertrophy, developmental delay, and dysmorphic features who presented to our center with hypoglycemic seizures at age 6 months. Critical sample revealed hypoketotic hypoglycemia, undetectable insulin, and suppressed free fatty acids. Molecular testing confirmed a pathogenic c.49G>A, p.(Glu17Lys) AKT2 mutation. Glycemic control was initially difficult to establish, with recurrent hypoglycemia despite high glucose infusion rates. Following in-hospital administration of waxy maize heat-modified starch at age 4-years, she remained euglycemic overnight, despite a previous report showing no benefit compared to uncooked cornstarch in an infant with the same mutation. Our report suggests waxy maize heat-modified starch is a viable treatment option for patients with activating c.49G>A AKT2 mutations and provides further evidence of a broad phenotypic spectrum.

Doxorubicin (DOX), a widely used chemotherapy agent in cancer treatment, encounters limitations in clinical efficacy due to associated cardiotoxicity. This study aims to explore the role of AKT serine/threonine kinase 2 (AKT2) in mitigating DOX-induced oxidative stress within the heart through both intracellular and extracellular signaling pathways. Utilizing Akt2 knockout (KO) and Nrf2 KO murine models, alongside neonatal rat cardiomyocytes (NRCMs), we systematically investigate the impact of AKT2 deficiency on DOX-induced cardiac injury. Our findings reveal that DOX administration induces significant oxidative stress, a primary contributor to cardiac injury. Importantly, Akt2 deficiency exhibits a protective effect by alleviating DOX-induced oxidative stress. Mechanistically, Akt2 deficiency facilitates nuclear translocation of NRF2, thereby suppressing intracellular oxidative stress by promoting the expression of antioxidant genes. Furthermore, We also observed that AKT2 inhibition facilitates superoxide dismutase 2 (SOD2) expression both inside macrophages and SOD2 secretion to the extracellular matrix, which is involved in lowering oxidative stress in cardiomyocytes upon DOX stimulation. The present study underscores the important role of AKT2 in mitigating DOX-induced oxidative stress through both intracellular and extracellular signaling pathways. Additionally, our findings propose promising therapeutic strategies for addressing DOX-induced cardiomyopathy in clinic.

Due to soared obesity population worldwide, hepatosteatosis is becoming a major risk factor for hepatocellular carcinoma (HCC). Undertaken molecular events during the progression of steatosis to liver cancer are thus under intensive investigation. In this study, we demonstrated that high-fat diet potentiated mouse liver AKT2. Hepatic AKT2 hyperactivation through gain-of-function mutation of Akt2 (Akt2E17K) caused spontaneous hepatosteatosis, injury, inflammation, fibrosis, and eventually HCC in mice. AKT2 activation also exacerbated lipopolysaccharide and D-galactosamine hydrochloride-induced injury/inflammation and N-Nitrosodiethylamine (DEN)-induced HCC. A positive correlation between AKT2 activity and SCD1 expression was observed in human HCC samples. Activated AKT2 enhanced the production of monounsaturated fatty acid which was dependent on SREBP1 upregulation of SCD1. Blockage of active SREBP1 and ablation of SCD1 reduced steatosis, inflammation, and tumor burden in DEN-treated Akt2E17K mice. Therefore, AKT2 activation is crucial for the development of steatosis-associated HCC which can be treated with blockage of AKT2-SREBP1-SCD1 signaling cascade.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive disease with an abnormal accumulation of fibrotic tissue in the lung parenchyma and elevated glycolysis level in associated cells without effective therapy options. Lactate accumulation in pulmonary fibrotic tissue is a significant factor aggravating IPF development, but the main mechanism regulating glycolysis needs further investigation. In this study, lung fibrosis model was induced by bleomycin (BLM) intratracheally in female C57BL/6 mice. The changes of lactate level and fibrotic markers were detected. For in vitro studies, cell lines of alveolar epithelial cell and lung fibroblast cell were stimulated with TGF-β1 and BLM respectively, to detect changes in their fibrotic properties. The function of lactate accumulation on facilitating fibrosis was verified. We demonstrated that BLM-induced pulmonary fibrosis is accompanied by lactate accumulation owing to glycolysis upregulation. Significantly high PDK1 expression in lung fibrotic tissue promotes glycolysis. Moreover, PDK1 stimulated trans-differentiation of lung fibroblasts and epithelial-mesenchymal transition (EMT) of alveolar epithelial cells. Furthermore, phosphorylated Akt2 activated PDK1 to cause pulmonary fibrosis and inhibitors of Akt2 and PDK1 could suppress fibrotic process. This study is the first to consider PDK1 facilitated lactate accumulation through glycolysis as a vital factor in pulmonary fibrosis and could be initiated by Akt2. We concluded that the pro-fibrotic properties of PDK1 are associated with Akt2 phosphorylation and thus provide new potential therapeutic targets for pulmonary fibrosis.