PI3K/Akt: getting it right matters

Brain insulin resistance in Down syndrome: Involvement of PI3K-Akt/mTOR axis in early-onset of Alzheimer's disease and its potential as a therapeutic target

Down syndrome (DS) is the most common genetic cause of intellectual impairment, characterised by an extra copy of chromosome 21. After the age of 40, DS individuals are highly susceptible to accelerated ageing and the development of early-onset Alzheimer-like neuropathology. In the context of DS, the brain presents a spectrum of neuropathological mechanisms and metabolic anomalies. These include heightened desensitisation of brain insulin and insulin-like growth factor-1 (IGF-1) reactions, compromised mitochondrial functionality, escalated oxidative stress, reduced autophagy, and the accumulation of amyloid beta and tau phosphorylation. These multifaceted factors intertwine to shape the intricate landscape of DS-related brain pathology. Altered brain insulin signalling is linked to Alzheimer's disease (AD). This disruption may stem from anomalies in the extracellular aspect (insulin receptor) or the intracellular facet, involving the inhibition of insulin receptor substrate 1 (IRS1). Both domains contribute to the intricate mechanism underlying this dysregulation. The PI3K-Akt/mammalian target of the rapamycin (mTOR) axis is a crucial intracellular element of the insulin signalling pathway that connects numerous physiological processes in the cell cycle. In age-related neurodegenerative disorders like AD, aberrant modulation of the PI3K-Akt signalling cascade is a key factor contributing to their onset. Aberrant and sustained hyperactivation of the PI3K/Akt-mTOR axis in the DS brain is implicated in early symptoms of AD development. Targeting the PI3K-Akt/mTOR pathway may help delay the onset of early-onset AD in individuals with DS, offering a potential way to slow disease progression and enhance their quality of life.

Designing and the anticancer activity of chitosan and chitosan oligosaccharide lactate nanobeads loaded with Biginelli hybrid

This study focuses on the designing and characterization, and anticancer evaluation of chitosan-based nanoparticles (NPs) loaded (enriched) with a Biginelli hybrid compound (BH). NPs based on chitosan (CH) or chitosan oligosaccharide lactate (CHOL), are carefully designed to encapsulate a tetrahydropyrimidine derivative (BH) with already proven anticancer properties. The formulations were evaluated for their physicochemical properties, including particle size distribution and morphology, using techniques such as infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. The cytotoxicity profiles were assessed on different cancer cell lines, showing a higher selectivity towards HeLa and A549 cells related to BH. BH-CH showed better cytotoxic profile related to BH-CHOL NPs. A cell cycle analysis revealed an accumulation of cells in the G2/M phase after a treatment with these NPs, indicating the ability to induce mitotic arrest in cancer cells. In summary, the results underscore the promising application of CH-based natural nanocarriers for the targeted delivery of Biginelli hybrids, showcasing a significant potential for further in vivo testing.

Emerging and reemerging infectious diseases: global trends and new strategies for their prevention and control

To adequately prepare for potential hazards caused by emerging and reemerging infectious diseases, the WHO has issued a list of high-priority pathogens that are likely to cause future outbreaks and for which research and development (R&D) efforts are dedicated, known as paramount R&D blueprints. Within R&D efforts, the goal is to obtain effective prophylactic and therapeutic approaches, which depends on a comprehensive knowledge of the etiology, epidemiology, and pathogenesis of these diseases. In this process, the accessibility of animal models is a priority bottleneck because it plays a key role in bridging the gap between in-depth understanding and control efforts for infectious diseases. Here, we reviewed preclinical animal models for high priority disease in terms of their ability to simulate human infections, including both natural susceptibility models, artificially engineered models, and surrogate models. In addition, we have thoroughly reviewed the current landscape of vaccines, antibodies, and small molecule drugs, particularly hopeful candidates in the advanced stages of these infectious diseases. More importantly, focusing on global trends and novel technologies, several aspects of the prevention and control of infectious disease were discussed in detail, including but not limited to gaps in currently available animal models and medical responses, better immune correlates of protection established in animal models and humans, further understanding of disease mechanisms, and the role of artificial intelligence in guiding or supplementing the development of animal models, vaccines, and drugs. Overall, this review described pioneering approaches and sophisticated techniques involved in the study of the epidemiology, pathogenesis, prevention, and clinical theatment of WHO high-priority pathogens and proposed potential directions. Technological advances in these aspects would consolidate the line of defense, thus ensuring a timely response to WHO high priority pathogens.

Akt1 deficiency does not affect fiber type composition or mitochondrial protein expression in skeletal muscle of male mice

Insulin-like growth factor-1-induced activation of ATP citrate lyase (ACLY) improves muscle mitochondrial function through an Akt-dependent mechanism. In this study, we examined whether Akt1 deficiency alters skeletal muscle fiber type and mitochondrial function by regulating ACLY-dependent signaling in male Akt1 knockout (KO) mice (12-16 weeks old). Akt1 KO mice exhibited decreased body weight and muscle wet weight, with reduced cross-sectional areas of slow- and fast-type muscle fibers. Loss of Akt1 did not affect the phosphorylation status of ACLY in skeletal muscle. The skeletal muscle fiber type and expression of mitochondrial oxidative phosphorylation complex proteins were unchanged in Akt1 KO mice compared with the wild-type control. These observations indicate that Akt1 is important for the regulation of skeletal muscle fiber size, whereas the regulation of muscle fiber type and muscle mitochondrial content occurs independently of Akt1 activity.

A comprehensive review of the PTEN/PI3K/Akt axis in multiple myeloma: From molecular interactions to potential therapeutic targets

Phosphatase and tensin homolog (PTEN), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (Akt) signaling pathways contribute to the development of several cancers, including multiple myeloma (MM). PTEN is a tumor suppressor that influences the PI3K/Akt/mTOR pathway, which in turn impacts vital cellular processes like growth, survival, and treatment resistance. The current study aims to present the role of PTEN and PI3K/Akt/mTOR signaling in the development of MM and its response to treatment. In addition, the molecular interactions in MM that underpin the PI3K/Akt/mTOR pathway and address potential implications for the development of successful treatment plans are also discussed in detail. We investigate their relationship to both upstream and downstream regulators, highlighting new developments in combined therapies that target the PTEN/PI3K/Akt axis to overcome drug resistance, including the use of PI3K and mitogen-activated protein kinase (MAPK) inhibitors. We also emphasize that PTEN/PI3K/Akt pathway elements may be used in MM diagnosis, prognosis, and therapeutic targets.

Inhibition of STAT3: A promising approach to enhancing the efficacy of chemotherapy in medulloblastoma

Medulloblastoma is a type of brain cancer that primarily affects children. While chemotherapy has been shown to be effective in treating medulloblastoma, the development of chemotherapy resistance remains a challenge. One potential therapeutic approach is to selectively inhibit the inducible transcription factor called STAT3, which is known to play a crucial role in the survival and growth of tumor cells. The activation of STAT3 has been linked to the growth and progression of various cancers, including medulloblastoma. Inhibition of STAT3 has been shown to sensitize medulloblastoma cells to chemotherapy, leading to improved treatment outcomes. Different approaches to STAT3 inhibition have been developed, including small-molecule inhibitors and RNA interference. Preclinical studies have shown the efficacy of STAT3 inhibitors in medulloblastoma, and clinical trials are currently ongoing to evaluate their safety and effectiveness in patients with various solid tumors, including medulloblastoma. In addition, researchers are also exploring ways to optimize the use of STAT3 inhibitors in combination with chemotherapy and identify biomarkers that can predict treatment that will help to develop personalized treatment strategies. This review highlights the potential of selective inhibition of STAT3 as a novel approach for the treatment of medulloblastoma and suggests that further research into the development of STAT3 inhibitors could lead to improved outcomes for patients with aggressive cancer.

Potential Wound Healing and Anti-Melanogenic Activities in Skin Cells of Aralia elata (Miq.) Seem. Flower Essential Oil and Its Chemical Composition

Aralia elata (Miq.) Seem. (AES; family Araliaceae) is a medicinal plant and has been reported to have various bioactivities, including anticancer and hepatotoxicity protective activities. However, no studies have investigated the biological activities of AES or its extracts on skin. To address this, we aimed to explore the effect of AES-flower-derived absolute-type essential oil (AESFEO) on skin-related biological activities, especially skin wound healing and whitening-related responses in skin cells (human-derived keratinocytes [HaCaT cells] and melanocytes [B16BL6 cells]) and to identify the components of AESFEO. Cell biological activities were analyzed using WST and BrdU incorporation assays, ELISA, or by immunoblotting. In HaCaT cells, AESFEO promoted proliferation, type IV collagen production, and enhanced the phosphorylations of Erk1/2, p38 MAPK, JNK, and Akt. In B16BL6 cells, AESFEO reduced serum-induced proliferation, α-MSH-stimulated increases in melanin synthesis and tyrosinase activity, and α-MSH-induced increases in MITF, tyrosinase, TRP-1, and TRP-2 expressions. In addition, AESFEO inhibited the phosphorylation of Erk1/2, p38 MAPK, and JNK in α-MSH-stimulated B16BL6 cells. Eighteen compounds were identified in AESFEO by GC/MS. These results suggest that AESFEO has beneficial effects on keratinocyte activities related to skin wound healing and melanocyte activities related to inhibition of skin pigmentation. AESFEO may serve as a useful natural substance for developing agents that facilitate skin wound healing and inhibit melanogenesis.

Revealing the Potency of Growth Factors in Bovine Colostrum

Colostrum is a nutritious milk synthesized by mammals during the postpartum period, and its rich bioactive components has led to a global increase in the consumption of bovine colostrum as a supplement. Bovine colostrum contains key components such as immunoglobulins, oligosaccharides, lactoferrin and lysozyme. It is a special supplement source due to its natural, high bioavailability and high concentrations of growth factors. Growth factors are critical to many physiological functions, and considering its presence in the colostrum, further research must be conducted on its safe application in many bodily disorders. Growth factors contribute to wound healing, muscle and bone development, and supporting growth in children. Additionally, the molecular mechanisms have been explored, highlighting the growth factors roles in cell proliferation, tissue regeneration, and the regulation of immune responses. These findings are crucial for understanding the potential health effects of bovine colostrum, ensuring its safe use, and forming a basis for future clinical applications. This review article examines the growth factors concentration in bovine colostrum, their benefits, clinical studies, and molecular mechanisms.

Single-cell transcriptomic Atlas of aging macaque ocular outflow tissues

The progressive degradation in the trabecular meshwork (TM) is related to age-related ocular diseases like primary open-angle glaucoma. However, the molecular basis and biological significance of the aging process in TM have not been fully elucidated. Here, we established a dynamic single-cell transcriptomic landscape of aged macaque TM, wherein we classified the outflow tissue into 12 cell subtypes and identified mitochondrial dysfunction as a prominent feature of TM aging. Furthermore, we divided TM cells into 13 clusters and performed an in-depth analysis on cluster 0, which had the highest aging score and the most significant changes in cell proportions between the two groups. Ultimately, we found that the APOE gene was an important differentially expressed gene in cluster 0 during the aging process, highlighting the close relationship between cell migration and extracellular matrix regulation, and TM function. Our work further demonstrated that silencing the APOE gene could increase migration and reduce apoptosis by releasing the inhibition on the PI3K-AKT pathway and downregulating the expression of extracellular matrix components, thereby increasing the aqueous outflow rate and maintaining intraocular pressure within the normal range. Our work provides valuable insights for future clinical diagnosis and treatment of glaucoma.

Post-translational control of NLRP3 inflammasome signaling

Inflammasomes serve as critical sensors for disruptions to cellular homeostasis, with inflammasome assembly leading to inflammatory caspase activation, gasdermin cleavage, and cytokine release. While the canonical pathways leading to priming, assembly, and pyroptosis are well characterized, recent work has begun to focus on the role of post-translational modifications (PTMs) in regulating inflammasome activity. A diverse array of PTMs, including phosphorylation, ubiquitination, SUMOylation, acetylation, and glycosylation, exert both activating and inhibitory influences on members of the inflammasome cascade through effects on protein-protein interactions, stability, and localization. Dysregulation of inflammasome activation is associated with a number of inflammatory diseases, and evidence is emerging that aberrant modification of inflammasome components contributes to this dysregulation. This review provides insight into PTMs within the NLRP3 inflammasome pathway and their functional consequences on the signaling cascade and highlights outstanding questions that remain regarding the complex web of signals at play.

TGF-β signaling in health, disease, and therapeutics

Transforming growth factor (TGF)-β is a multifunctional cytokine expressed by almost every tissue and cell type. The signal transduction of TGF-β can stimulate diverse cellular responses and is particularly critical to embryonic development, wound healing, tissue homeostasis, and immune homeostasis in health. The dysfunction of TGF-β can play key roles in many diseases, and numerous targeted therapies have been developed to rectify its pathogenic activity. In the past decades, a large number of studies on TGF-β signaling have been carried out, covering a broad spectrum of topics in health, disease, and therapeutics. Thus, a comprehensive overview of TGF-β signaling is required for a general picture of the studies in this field. In this review, we retrace the research history of TGF-β and introduce the molecular mechanisms regarding its biosynthesis, activation, and signal transduction. We also provide deep insights into the functions of TGF-β signaling in physiological conditions as well as in pathological processes. TGF-β-targeting therapies which have brought fresh hope to the treatment of relevant diseases are highlighted. Through the summary of previous knowledge and recent updates, this review aims to provide a systematic understanding of TGF-β signaling and to attract more attention and interest to this research area.

The interplay of PTEN and AKT nexus in breast cancer: a molecular perspective

BACKGROUND

Breast cancer is a highly prevalent and life-threatening ailment that is commonly detected among the females. The downregulation of PTEN in breast cancer is associated with a poor prognosis, aggressive tumor type, and metastasis to lymph nodes, as it activates the pro-survival pathway PI3K/AKT, which is considered the ultimate proliferative pathway.

MATERIAL AND METHODS

The mRNA expression of PTEN and AKT genes was investigated using RT-qPCR and TaqMan primer probe chemistry. Moreover DNA was also isolated from the same tissue samples and exonic regions of both genes were amplified for mutational analysis. The proteins expression of PTEN and AKT from seven human breast cancer cell lines was checked through western blot experiments.

RESULT

The study revealed a decrease in PTEN expression in 73.3% of the samples, whereas an increase in AKT expression in 40% of samples was observed when compared to the distant normal breast tissue. Conversely, the remaining 60% of samples exhibited a decrease in AKT mRNA expression. There was no observed alteration in the genetic sequence of AKT and PTEN within the targeted amplified regions of breast cancer samples. The high levels of PTEN protein in T-47D and MDA-MB-453 resulted in a lower p-AKT. Two cell lines ZR-75-1 and MDA-MB-468 appeared to be PTEN negative on western blot but mRNA was detected on RT-qPCR.

CONCLUSION

In breast cancer the status/expression of PTEN & AKT at mRNA and protein level might be obliging in forecasting the path of disease progression, treatment and prognosis.

Network pharmacology, molecular docking and experimental verification of the mechanism of huangqi-jixuecao herb pair in treatment of peritoneal fibrosis

ETHNOPHARMACOLOGICAL RELEVANCE

The Huangqi-Jixuecao herb pair (HQJXCHP) is a traditional herbal formula composed of two widely applied TCM prescriptions, Huangqi (Astragalus membranaceus (Fisch.) Bunge) and Jixuecao (Centella asiatica (L.) Urb.), used for hundreds of years to replenish qi and clear away heat. However, the therapeutic effects of HQJXCHP against peritoneal fibrosis (PF) and potential targets are currently unclear.

AIMS OF THE STUDY

The main objective of this study was preliminary prediction and validation of the effects and molecular mechanisms of action of HQJXCHP against PF based on network pharmacology analysis and experimental verification.

MATERIALS AND METHODS

The ingredients of HQJXCHP were analyzed via HPLC-Q-TOF/MS. Bioactive compounds of HQJXCHP used for network pharmacology analysis were obtained from the TCMSP database. HQJXCHP-related therapeutic targets in PF were obtained from the GeneCards, OMIM, Therapeutic Targets and PharmGkb databases. Therapeutic target-related signaling pathways were predicted via GO and KEGG pathway enrichment analyses. The targets of HQJXCHO were further validated in a PDS-induced PF mouse model in vivo and PMCs MMT model in vitro.

RESULTS

A total of 23 bioactive compounds of HQJXCHP related 188 target genes were retrieved. The HQJXCHP compound-target and PF-related target networks identified 131 common target genes. Subsequent protein-protein interaction (PPI) network analysis results disclosed Akt1, TP53, TNF, VEGFA and CASP3 as the top five key targets of HQJXCHP. Further molecular docking data revealed strong affinity of the two key compounds of HQJXCHP, quercetin and kaempferol, for these key targets. GO and KEGG pathway enrichment analyses further showed that PI3K/Akt, IL-17, TNF and TLR pathways contribute to the therapeutic effects of HQJXCHP on PF. An in vivo PDS-induced PF mouse model and in vitro PMCs mesothelial-to-mesenchymal transition (MMT) model with or without HQJXCHP intervention were used to confirm the effects and mechanisms of action of HQJXCHP. Western blot and qRT-PCR results showed that HQ, JXC and HQJXCHP reduced PDS-induced inflammatory cell aggregation and peritoneal thickening through suppressing the MMT process, among which HQJXCHP exerted the greatest therapeutic effect. Moreover, HQJXCHP inhibited activation of the PI3K/Akt, IL-17, TNF and TLR signaling pathways induced by PDS.

CONCLUSIONS

This is the first study to employ network pharmacology and molecular docking analyses to predict the targets of HQJXCHP with therapeutic effects on PDS-related PF. Data from in vivo and in vitro validation experiments collectively showed that HQJXCHP delays the PF process through inhibiting PI3K/Akt, IL-17, TNF and TLR signaling pathways. Overall, our findings highlight the successful application of network pharmacology theory to provide a scientific basis for clinical utility of HQJXCHP against PF.

The pharmacological effects of Berberine and its therapeutic potential in different diseases: Role of the phosphatidylinositol 3-kinase/AKT signaling pathway

The phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway plays a central role in cell growth and survival and is disturbed in various pathologies. The PI3K is a kinase that generates phosphatidylinositol-3,4,5-trisphosphate (PI (3-5) P3), as a second messenger responsible for the translocation of AKT to the plasma membrane and its activation. However, due to the crucial role of the PI3K/AKT pathway in regulation of cell survival processes, it has been introduced as a main therapeutic target for natural compounds during the progression of different pathologies. Berberine, a plant-derived isoquinone alkaloid, is known because of its anti-inflammatory, antioxidant, antidiabetic, and antitumor properties. The effect of this natural compound on cell survival processes has been shown to be mediated by modulation of the intracellular pathways. However, the effects of this natural compound on the PI3K/AKT pathway in various pathologies have not been reviewed so far. Therefore, this paper aims to review the PI3K/AKT-mediated effects of Berberine in different types of cancer, diabetes, cardiovascular, and central nervous system diseases.

An Alzheimer's disease risk variant in TTC3 modifies the actin cytoskeleton organization and the PI3K-Akt signaling pathway in iPSC-derived forebrain neurons

A missense variant in the tetratricopeptide repeat domain 3 (TTC3) gene (rs377155188, p.S1038C, NM_003316.4:c 0.3113C>G) was found to segregate with disease in a multigenerational family with late-onset Alzheimer's disease. This variant was introduced into induced pluripotent stem cells (iPSCs) derived from a cognitively intact individual using CRISPR genome editing, and the resulting isogenic pair of iPSC lines was differentiated into cortical neurons. Transcriptome analysis showed an enrichment for genes involved in axon guidance, regulation of actin cytoskeleton, and GABAergic synapse. Functional analysis showed that the TTC3 p.S1038C iPSC-derived neuronal progenitor cells had altered 3-dimensional morphology and increased migration, while the corresponding neurons had longer neurites, increased branch points, and altered expression levels of synaptic proteins. Pharmacological treatment with small molecules that target the actin cytoskeleton could revert many of these cellular phenotypes, suggesting a central role for actin in mediating the cellular phenotypes associated with the TTC3 p.S1038C variant.

Advanced in vitro models for renal cell carcinoma therapy design

Renal cell carcinoma (RCC) and its principal subtype, clear cell RCC, are the most diagnosed kidney cancer. Despite substantial improvement over the last decades, current pharmacological intervention still fails to achieve long-term therapeutic success. RCC is characterized by a high intra- and inter-tumoral heterogeneity and is heavily influenced by the crosstalk of the cells composing the tumor microenvironment, such as cancer-associated fibroblasts, endothelial cells and immune cells. Moreover, multiple physicochemical properties such as pH, interstitial pressure or oxygenation may also play an important role. These elements are often poorly recapitulated in in vitro models used for drug development. This inadequate recapitulation of the tumor is partially responsible for the current lack of an effective and curative treatment. Therefore, there are needs for more complex in vitro or ex vivo drug screening models. In this review, we discuss the current state-of-the-art of RCC models and suggest strategies for their further development.

Integrated Transcriptome and Molecular Docking to Identify the Hub Superimposed Attenuation Targets of Curcumin in Breast Cancer Cells

Numerous in vitro and in vivo studies have shown that curcumin primarily activates apoptotic pathways in cancer cells and inhibits cancer progression by modulating various molecular targets. In this study, we utilized reverse docking servers to predict 444 human proteins that may potentially be targeted by curcumin. Then, high-throughput assays were conducted by using RNA-seq technology on curcumin-treated MCF-7 (human breast cancer ER (+)) and MDA-MB-231 (human breast cancer ER(-)/TNBC) cancer cell lines. Enrichment analysis identified seven and eight significantly down-regulated signaling pathways in these two cell lines, where the enriched genes were used to construct protein-protein interaction networks. From these networks, the MCODE algorithm screened out 42 hub targets, which are core genes of the RTK-(PI3K-AKT)/(MEK/ERK1/2) crosstalk network. Genetic alteration and expression patterns of hub targets of curcumin may be closely related to the overall pathogenesis and prognosis of breast cancer. MAPKAPK3, AKT3, CDK5, IGF1R, and MAPK11 are potential prognostic markers and therapeutic targets of curcumin in patients with triple-negative breast cancer. Molecular docking and transcriptomic results confirmed that curcumin can inhibit these high-scoring targets at the protein level. Additionally, these targets can act as self-feedback factors, relying on the cascading repressive effects in the network to limit their own transcription at the mRNA level. In conclusion, the integration of transcriptomic and molecular docking approaches enables the rapid identification of dual or multiple inhibitory targets of curcumin in breast cancer. Our study provides the potential elucidation of the anti-cancer mechanism of curcumin.

Myricitrin promotes osteogenesis and prevents ovariectomy bone mass loss via the PI3K/AKT signalling pathway

This study aimed to explore the effect of myricitrin on osteoblast differentiation in mice immortalised bone marrow mesenchymal stem cells (imBMSCs). Additionally, ovariectomy (OVX) mice were employed to examine the effect of myricitrin on bone trabecular loss in vivo. The effect of myricitrin on the proliferation of imBMSCs was evaluated using a cell counting kit-8 assay. Alizarin red staining, alkaline phosphatase staining were performed to elucidate osteogenesis. Furthermore, qRT-PCR and western blot determined the expression of osteo-specific genes and proteins. To screen for candidate targets, mRNA transcriptome genes were sequenced using bioinformatics analyses. Western blot and molecular docking analysis were used to examine target signalling markers. Moreover, rescue experiments were used to confirm the effect of myricitrin on the osteogenic differentiation of imBMSCs. OVX mice were also used to estimate the delay capability of myricitrin on bone trabecular loss in vivo using western blot, micro-CT, tartaric acid phosphatase (Trap) staining, haematoxylin and eosin staining, Masson staining and immunochemistry. In vitro, myricitrin significantly enhanced osteo-specific genes and protein expression and calcium deposition. Moreover, mRNA transcriptome gene sequencing and molecular docking analysis revealed that this enhancement was accompanied by an upregulation of the PI3K/AKT signalling pathway. Furthermore, copanlisib, a PI3K inhibitor, partially reversed the osteogenesis promotion induced by myricitrin. In vivo, western blot, micro-CT, hematoxylin and eosin staining, Masson staining, Trap staining and immunochemistry revealed that bone trabecular loss rate was significantly alleviated in the myricitrin low- and high-dose groups, with an increased expression of osteopontin, osteoprotegerin, p-PI3K and p-AKT compared to the OVX group. Myricitrin enhances imBMSC osteoblast differentiation and attenuate bone mass loss partly through the upregulation of the PI3K/AKT signalling pathway. Thus, myricitrin has therapeutic potential as an antiosteoporosis drug.

Pulsed frequency modulated ultrasound promotes therapeutic effects of osteoporosis induced by ovarian failure in mice

Low-intensity pulsed ultrasound (LIPUS) has been proved to be an effective technique for the treatment of osteoporosis. To better activate the bone formation-related markers, promote the different stages of osteogenesis, and further enhance the therapeutic effects of ultrasound, this study employed pulsed frequency modulated ultrasound (pFMUS) to treat mice with osteoporosis, which was caused by ovarian failure due to 4-vinylcyclohexene dioxide (VCD) injection. Healthy 8-week-old female C57BL/6J mice were randomly divided into four groups: Sham (S), VCD-control (V), VCD + LIPUS (VU), and VCD + pFMUS (VFU). VU and VFU groups were treated by LIPUS and pFMUS, respectively. Serum analysis, micro-computed tomography (micro-CT), mechanical testing and hematoxylin and eosin (HE) staining were performed to evaluate the therapeutic effects of ultrasound. Quantitative reverse-transcription PCR (qRT-PCR) and western blot analysis were used to explore the mechanism of ultrasound on osteoporosis. Results showed that pFMUS might have better therapeutic effects than traditional LIPUS in terms of bone microstructure and bone strength. In addition, pFMUS could promote bone formation by activating phosphoinositide-3 kinase/protein kinase B (PI3K/Akt) pathway, and slow down bone resorption by increasing osteoprotegerin/receptor activator of nuclear factor κB ligand (OPG/RANKL) ratio. This study is of positive prognostic significance when understanding the mechanism of ultrasound regulation on osteoporosis and establishing novel treatment plan of osteoporosis by multi-frequency ultrasound.

Phosphoinositide 3-kinase (PI3K) classes: From cell signaling to endocytic recycling and autophagy

Lipid signaling is defined as any biological signaling action in which a lipid messenger binds to a protein target, converting its effects to specific cellular responses. In this complex biological pathway, the family of phosphoinositide 3-kinase (PI3K) represents a pivotal role and affects many aspects of cellular biology from cell survival, proliferation, and migration to endocytosis, intracellular trafficking, metabolism, and autophagy. While yeasts have a single isoform of phosphoinositide 3-kinase (PI3K), mammals possess eight PI3K types divided into three classes. The class I PI3Ks have set the stage to widen research interest in the field of cancer biology. The aberrant activation of class I PI3Ks has been identified in 30-50% of human tumors, and activating mutations in PIK3CA is one of the most frequent oncogenes in human cancer. In addition to indirect participation in cell signaling, class II and III PI3Ks primarily regulate vesicle trafficking. Class III PI3Ks are also responsible for autophagosome formation and autophagy flux. The current review aims to discuss the original data obtained from international research laboratories on the latest discoveries regarding PI3Ks-mediated cell biological processes. Also, we unravel the mechanisms by which pools of the same phosphoinositides (PIs) derived from different PI3K types act differently.

An Alzheimer's disease risk variant in TTC3 modifies the actin cytoskeleton organization and the PI3K-Akt signaling pathway in iPSC-derived forebrain neurons

A missense variant in the tetratricopeptide repeat domain 3 ( TTC3 ) gene (rs377155188, p.S1038C, NM_003316.4:c.3113C>G) was found to segregate with disease in a multigenerational family with late onset Alzheimer's disease. This variant was introduced into induced pluripotent stem cells (iPSCs) derived from a cognitively intact individual using CRISPR genome editing and the resulting isogenic pair of iPSC lines were differentiated into cortical neurons. Transcriptome analysis showed an enrichment for genes involved in axon guidance, regulation of actin cytoskeleton, and GABAergic synapse. Functional analysis showed that the TTC3 p.S1038C iPSC-derived neuronal progenitor cells had altered 3D morphology and increased migration, while the corresponding neurons had longer neurites, increased branch points, and altered expression levels of synaptic proteins. Pharmacological treatment with small molecules that target the actin cytoskeleton could revert many of these cellular phenotypes, suggesting a central role for actin in mediating the cellular phenotypes associated with the TTC3 p.S1038C variant.

Highlights

The AD risk variant TTC3 p.S1038C reduces the expression levels of TTC3 The variant modifies the expression of AD specific genes BACE1 , INPP5F , and UNC5C Neurons with the variant are enriched for genes in the PI3K-Akt pathwayiPSC-derived neurons with the alteration have increased neurite length and branchingThe variant interferes with actin cytoskeleton and is ameliorated by Cytochalasin D.

Loss of PI3k activity of inositol polyphosphate multikinase impairs PDK1-mediated AKT activation, cell migration, and intestinal homeostasis

Protein kinase B (AKT) is essential for cell survival, proliferation, and migration and has been associated with several diseases. Here, we demonstrate that inositol polyphosphate multikinase (IPMK's) lipid kinase property drives AKT activation via increasing membrane localization and activation of PDK1 (3-Phosphoinositide-dependent kinase 1), largely independent of class I PI3k (cPI3K). Deletion of IPMK impairs cell migration, which is partially associated with the abolition of PDK1-mediated ROCK1 disinhibition and subsequent myosin light chain (MLC) phosphorylation. IPMK is highly expressed in intestinal epithelial cells (IEC). Deleting IPMK in IEC reduced AKT phosphorylation and diminished the number of Paneth cells. Ablation of IPMK impaired IEC regeneration both basally and after chemotherapy-induced damage, suggesting a broad role for IPMK in activating AKT and intestinal tissue regeneration. In conclusion, the PI3k activity of IPMK is necessary for PDK1-mediated AKT activation and intestinal homeostasis.

Short interfering RNA in colorectal cancer: is it wise to shoot the messenger?

Colorectal cancer (CRC) is the third most common cancer and the leading cause of gastrointestinal cancer death. 90% of people diagnosed with colorectal cancer are over the age of 50; nevertheless, the illness is more aggressive among those detected at a younger age. Chemotherapy-based treatment has several adverse effects on both normal and malignant cells. The primary signaling pathways implicated in the advancement of CRC include hedgehog (Hh), janus kinase and signal transducer and activator of transcription (JAK/STAT), Wingless-related integration site (Wnt)/β-catenin, transforming growth factor-β (TNF-β), epidermal growth factor receptor (EGFR)/Mitogen-activated protein kinases (MAPK), phosphoinositide 3-kinase (PI3K), nuclear factor kappa B (NF-κB), and Notch. Loss of heterozygosity in tumor suppressor genes like adenomatous polyposis coli, as well as mutation or deletion of genes like p53 and Kirsten rat sarcoma viral oncogene (KRAS), are all responsible for the occurrence of CRC. Novel therapeutic targets linked to these signal-transduction cascades have been identified as a consequence of advances in small interfering RNA (siRNA) treatments. This study focuses on many innovative siRNA therapies and methodologies for delivering siRNA therapeutics to the malignant site safely and effectively for the treatment of CRC. Treatment of CRC using siRNA-associated nanoparticles (NPs) may inhibit the activity of oncogenes and MDR-related genes by targeting a range of signaling mechanisms. This study summarizes several siRNAs targeting signaling molecules, as well as the therapeutic approaches that might be employed to treat CRC in the future.

Pathogenesis of Zika Virus Infection

Zika virus (ZIKV) is an emerging virus from the Flaviviridae family that is transmitted to humans by mosquito vectors and represents an important health problem. Infections in pregnant women are of major concern because of potential devastating consequences during pregnancy and have been associated with microcephaly in newborns. ZIKV has a unique ability to use the host machinery to promote viral replication in a tissue-specific manner, resulting in characteristic pathological disorders. Recent studies have proposed that the host ubiquitin system acts as a major determinant of ZIKV tropism by providing the virus with an enhanced ability to enter new cells. In addition, ZIKV has developed mechanisms to evade the host immune response, thereby allowing the establishment of viral persistence and enhancing viral pathogenesis. We discuss recent reports on the mechanisms used by ZIKV to replicate efficiently, and we highlight potential new areas of research for the development of therapeutic approaches.

KRAS Mutations in Solid Tumors: Characteristics, Current Therapeutic Strategy, and Potential Treatment Exploration

Kristen rat sarcoma (KRAS) gene is one of the most common mutated oncogenes in solid tumors. Yet, KRAS inhibitors did not follow suit with the development of targeted therapy, for the structure of KRAS has been considered as being implausible to target for decades. Chemotherapy was the initial recommended therapy for KRAS-mutant cancer patients, which was then replaced by or combined with immunotherapy. KRAS G12C inhibitors became the most recent breakthrough in targeted therapy, with Sotorasib being approved by the Food and Drug Administration (FDA) based on its significant efficacy in multiple clinical studies. However, the subtypes of the KRAS mutations are complex, and the development of inhibitors targeting non-G12C subtypes is still at a relatively early stage. In addition, the monotherapy of KRAS inhibitors has accumulated possible resistance, acquiring the exploration of combination therapies or next-generation KRAS inhibitors. Thus, other non-target, conventional therapies have also been considered as being promising. Here in this review, we went through the characteristics of KRAS mutations in cancer patients, and the prognostic effect that it poses on different therapies and advanced therapeutic strategy, as well as cutting-edge research on the mechanisms of drug resistance, tumor development, and the immune microenvironment.

Downregulation of PI3K/AKT/mTOR Pathway in Juglone-Treated Bovine Oocytes

We have previously reported that juglone, a natural compound found in Juglandaceae with a wide range of biological activities, can reduces the developmental competence of bovine oocytes. In the current study, we investigated the possible mechanisms behind the toxicity of juglone and the relationship with PI3K/AKT/mTOR signaling during the in vitro maturation (IVM) of oocytes. Results show that oocyte exposure to juglone was associated with a significant decrease in filamentous actin (F-actin) accumulation. The RT-qPCR showed downregulation of the meiosis progression indicator GSK-3A, oocyte development marker BMP15, mitochondria fusion controlling MFN1, oxidative stress-related OGG1, and histone methylation-related EZH1, EZH2, SUZ12, G9a, and SUV39H2 genes in juglone-treated oocytes. In addition, glycolysis- (PFK1 and GLUT1), ATP synthesis- (ATPase8 and ATP5F1B), and OXPHOS-specific markers (SDHA and SDHD), as well as the oocyte survival regulators (SOD2, VEGF, and MAPK1) significantly decreased upon juglone treatment. Moreover, lower expression of PI3K, AKT, and mTOR was observed at the transcriptional and/or translational level(s). The autophagy markers LC3B and beclin-1 as well as the DNA damage-specific marker 8-OxoG displayed overexpression in juglone-exposed oocytes. Taken together, our results show that administration of juglone during the IVM can reduce the quality and developmental health of bovine oocytes through downregulation of the PI3K/AKT/mTOR pathway and its downstream signaling cascades.

A review of signal pathway induced by virulent protein CagA of Helicobacter pylori

Gastric cancer (GC), a common and high-mortality disease, still occupies an important position in current cancer research, and Helicobacter pylori (H. pylori) infection as its important risk factor has been a hot and challenging research area. Among the numerous pathogenic factors of H. pylori, the virulence protein CagA has been widely studied as the only bacterial-derived oncoprotein. It was found that CagA entering into gastric epithelial cells (GECs) can induce the dysregulation of multiple cellular pathways such as MAPK signaling pathway, PI3K/Akt signaling pathway, NF-κB signaling pathway, Wnt/β-catenin signaling pathway, JAK-STAT signaling pathway, Hippo signaling pathway through phosphorylation and non-phosphorylation. These disordered pathways cause pathological changes in morphology, adhesion, polarity, proliferation, movement, and other processes of GECs, which eventually promotes the occurrence of GC. With the deepening of H. pylori-related research, the research on CagA-induced abnormal signaling pathway has been updated and deepened to some extent, so the key signaling pathways activated by CagA are used as the main stem to sort out the pathogenesis of CagA in this paper, aiming to provide new strategies for the H. pylori infection and treatment of GC in the future.

Epigenetic regulation of radioresistance: insights from preclinical and clinical studies

INTRODUCTION

Oftentimes, radiation therapy (RT) is ineffective due to the development of radioresistance (RR). However, studies have shown that targeting epigenetic modifiers to enhance radiosensitivity represents a promising direction of clinical investigation.

AREAS COVERED

This review discusses the mechanisms by which epigenetic modifiers alter radiosensitivity through dysregulation of MAPK-ERK and AKT-mTOR signaling. Finally, we discuss the clinical directions for targeting epigenetic modifiers and current radiology techniques used in the clinic.

METHODOLOGY

We searched PubMed and ScienceDirect databases from April 4^th, 2022 to October 18^th, 2022. We examined 226 papers related to radioresistance, epigenetics, MAPK, and PI3K/AKT/mTOR signaling. 194 papers were selected for this review. Keywords used for this search include, 'radioresistance,' 'radiosensitivity,' 'radiation,' 'radiotherapy,' 'particle radiation,' 'photon radiation,' 'epigenetic modifiers,' 'MAPK,' 'AKT,' 'mTOR,' 'cancer,' and 'PI3K.' We examined 41 papers related to clinical trials on the aforementioned topics. Outcomes of interest were safety, overall survival (OS), dose-limiting toxicities (DLT), progression-free survival (PFS), and maximum tolerated dose (MTD).

EXPERT OPINION

Current studies focusing on epigenetic mechanisms of RR strongly support the use of targeting epigenetic modifiers as adjuvants to standard cancer therapies. To further the success of such treatments and their clinical benefit , both preclinical and clinical studies are needed to broaden the scope of known radioresistant mechanisms.

Targeting KRAS in PDAC: A New Way to Cure It?

Pancreatic cancer is one of the most intractable malignant tumors worldwide, and is known for its refractory nature and poor prognosis. The fatality rate of pancreatic cancer can reach over 90%. In pancreatic ductal carcinoma (PDAC), the most common subtype of pancreatic cancer, KRAS is the most predominant mutated gene (more than 80%). In recent decades, KRAS proteins have maintained the reputation of being “undruggable” due to their special molecular structures and biological characteristics, making therapy targeting downstream genes challenging. Fortunately, the heavy rampart formed by KRAS has been broken down in recent years by the advent of KRASG12C inhibitors; the covalent inhibitors bond to the switch-II pocket of the KRASG12C protein. The KRASG12C inhibitor sotorasib has been received by the FDA for the treatment of patients suffering from KRASG12C-driven cancers. Meanwhile, researchers have paid close attention to the development of inhibitors for other KRAS mutations. Due to the high incidence of PDAC, developing KRASG12D/V inhibitors has become the focus of attention. Here, we review the clinical status of PDAC and recent research progress in targeting KRASG12D/V and discuss the potential applications.

Synthesis, Molecular Docking, In Vitro and In Vivo Studies of Novel Dimorpholinoquinazoline-Based Potential Inhibitors of PI3K/Akt/mTOR Pathway

A (series) range of potential dimorpholinoquinazoline-based inhibitors of the PI3K/Akt/mTOR cascade was synthesized. Several compounds exhibited cytotoxicity towards a panel of cancer cell lines in the low and sub-micromolar range. Compound 7c with the highest activity and moderate selectivity towards MCF7 cells which express the mutant type of PI3K was also tested for the ability to inhibit PI3K-(signaling pathway) downstream effectors and associated proteins. Compound 7c inhibited the phosphorylation of Akt, mTOR, and S6K at 125–250 nM. It also triggered PARP1 cleavage, ROS production, and cell death via several mechanisms. Inhibition of PI3Kα was observed at a concentration of 7b 50 µM and of 7c 500 µM and higher, that can indicate minority PI3Kα as a target among other kinases in the titled cascade for 7c. In vivo studies demonstrated an inhibition of tumor growth in the colorectal tumor model. According to the docking studies, the replacement of the triazine core in gedatolisib (8) by a quinazoline fragment, and incorporation of a (hetero)aromatic unit connected with the carbamide group via a flexible spacer, can result in more selective inhibition of the PI3Kα isoform.

All-trans retinoic acid enhanced the antileukemic efficacy of ABT-199 in acute myeloid leukemia by downregulating the expression of S100A8

Acute myeloid leukemia (AML) is prone to relapse. Targeted therapy with a specific inhibitor of the anti-apoptotic protein Bcl-2 ABT-199 is an effective method for relapsed and refractory patients, but drug resistance is likely, which is primarily related to high Mcl-1 and S100A8 expression. All-trans retinoic acid (ATRA) can inhibit Bcl-2 and Mcl-1 expression. The study purpose was to determine whether ATRA can enhance the antileukemia effect of ABT-199 on AML cells. Our data showed that ATRA combined with ABT-199 exerts a synergistic antileukemic effect by inducing apoptosis and cell cycle arrest in AML. In vivo, combination therapy prolonged the survival of AML xenograft mice. The possible mechanism involves promoting apoptosis through downregulation of S100A8 expression by inhibiting the PI3K/AKT signaling pathway. This study provides a potential treatment strategy and theoretical support for overcoming the clinical ABT-199 resistance problem in AML patients.

SB332235, a CXCR2 antagonist, ameliorates thioacetamide-induced hepatic encephalopathy through modulation of the PI3K/AKT pathways in rats

RATIONALE

Hepatic encephalopathy (HE) is a neuropsychiatric disorder that results from either acute or chronic liver failure. CXCR2 plays an essential role in the pathophysiology of liver and brain diseases. In the present study, the potential beneficial effects of SB332235, a selective inhibitor of CXCR2, against HE were evaluated.

METHODS

HE was induced in male rats by thioacetamide injection (200 mg/kg, i.p.) at three alternative days. SB332235 was injected in rats 1 h before TAA at a dose of 1 and 3 mg/kg i.p.

RESULTS

SB332235 alleviated oxidative stress as shown by the decreased serum NO and reduced MDA, elevated GSH and SOD levels, and reduced TNF-α and NF-κB levels in both brain and liver tissues of rats. Additionally, SB332235 suppressed brain ASK-1, JNK, IL-8, and caspase-3 expression, and activated PI3K/AKT expression in brain tissues. Markers of brain dysfunction, such as ammonia, and markers of hepatic injury, such as LDH, albumin, bilirubin, γGT, AST, ALT, and ALP, were significantly ameliorated. Also, the protective effect of SB332235 was confirmed by histological examination of both brain and liver tissues.

CONCLUSIONS

Both doses (1 and 3 mg/kg) of SB332235 revealed significant hepatic/neuroprotective effects due to their anti-inflammatory, antioxidant, and antiapoptotic activities via activation of the PI3K/AKT pathway. Between the two, the 1 mg/kg dose provided significantly improved outcomes.

Modulation of IL-4/IL-13 cytokine signaling in the context of allergic disease

Aberrant activation of CD4 T_H2 cells and excessive production of T_H2 cytokines such as IL-4 and IL-13 have been implicated in the pathogenesis of allergic diseases. Generally, IL-4 and IL-13 utilize Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathways for induction of inflammatory gene expression and the effector functions associated with disease pathology in many allergic diseases. However, it is increasingly clear that JAK/STAT pathways activated by IL-4/IL-13 can themselves be modulated in the presence of other intracellular signaling programs, thereby changing the overall tone and/or magnitude of IL-4/IL-13 signaling. Apart from direct activation of the canonic JAK/STAT pathways, IL-4 and IL-13 also induce proinflammatory gene expression and effector functions through activation of additional signaling cascades. These alternative signaling cascades contribute to several specific aspects of IL-4/IL-13-associated cellular and molecular responses. A more complete understanding of IL-4/IL-13 signaling pathways, including the precise conditions under which noncanonic signaling pathways are activated, and the impact of these pathways on cellular- and host-level responses, will better allow us to design agents that target specific pathologic outcomes or tailor therapies for the treatment of uncommon disease endotypes.

Ribosomes and Ribosomal Proteins Promote Plasticity and Stemness Induction in Glioma Cells via Reprogramming

Glioblastoma multiforme (GBM) is a lethal tumor that develops in the adult brain. Despite advances in therapeutic strategies related to surgical resection and chemo-radiotherapy, the overall survival of patients with GBM remains unsatisfactory. Genetic research on mutation, amplification, and deletion in GBM cells is important for understanding the biological aggressiveness, diagnosis, and prognosis of GBM. However, the efficacy of drugs targeting the genetic abnormalities in GBM cells is limited. Investigating special microenvironments that induce chemo-radioresistance in GBM cells is critical to improving the survival and quality of life of patients with GBM. GBM cells acquire and maintain stem-cell-like characteristics via their intrinsic potential and extrinsic factors from their special microenvironments. The acquisition of stem-cell-like phenotypes and aggressiveness may be referred to as a reprogramming of GBM cells. In addition to protein synthesis, deregulation of ribosome biogenesis is linked to several diseases including cancer. Ribosomal proteins possess both tumor-promotive and -suppressive functions as extra-ribosomal functions. Incorporation of ribosomes and overexpression of ribosomal protein S6 reprogram and induce stem-cell-like phenotypes in GBM cells. Herein, we review recent literature and our published data on the acquisition of aggressiveness by GBM and discuss therapeutic options through reprogramming.

MicroRNA expression in male infertility

Male infertility is a multifactorial disorder that involves different physiopathological mechanisms and multiple genes. In this sense, we analyse the role of miRNAs in this pathology. Gene expression analysis can provide relevant information to detect biomarkers, signalling pathways, pathologic mechanisms, and potential therapeutic targets for the disease. In this review, we describe four miRNA microarrays related to patients who present infertility diseases, including azoospermia, asthenozoospermia, and oligoasthenozoospermic. We selected 13 miRNAs with altered expressions in testis tissue (hsa-miR-122-5p, hsa-miR-145-5p, hsa-miR-16-5p, hsa-miR-193a-3p, hsa-miR-19a-3p, hsa-miR-23a-3p, hsa-miR-30b-5p, hsa-miR-34b-5p, hsa-miR-34c-5p, hsa-miR-374b-5p, hsa-miR-449a, hsa-miR-574-3p and hsa-miR-92a-3p), and systematically examine the mechanisms of four relevant miRNAs (hsa-miR-16-5p, hsa-miR-19a-3p, hsa-miR-92a-3p and hsa-miR-30b-5p) which we found that regulated a large number of proteins. An interaction network was generated, and its connections allowed us to identify signalling pathways and interactions between proteins associated with male infertility. In this way, we confirm that the most affected and relevant pathway is the PI3K-Akt signalling.

MARCH1 silencing suppresses growth of oral squamous cell carcinoma through regulation of PHLPP2

PURPOSE

Oral squamous cell carcinoma (OSCC) is the most frequent type of oral cancer and is associated with high mortality. Membrane-associated ring-CH type finger 1 (MARCH1) is an E3 ubiquitin ligase with roles in immune regulation and cancer development. Whether MARCH1 has a specific role in OSCC, and if so through what mechanism, has not been explored.

METHODS

Immunohistochemistry was performed to examine MARCH1 expression in OSCC clinical samples and adjacent paracancerous tissues. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and Western blot were conducted to determine mRNA expression and protein levels, respectively. Knockdown and overexpression experiments were carried out to evaluate the effects of MARCH1 on proliferation and apoptosis. To test protein-protein interaction, co-immunoprecipitation assay was performed. Finally, tumor cell grafting was utilized to test the function of MARCH in vivo.

RESULTS

High MARCH1 expression in OSCC clinical samples correlated with poor patient prognosis. Functionally, MARCH1 knockdown in OSCC cells suppressed proliferation and promoted apoptosis, while MARCH1 overexpression displayed the opposite effects. We identified PH Domain And Leucine Rich Repeat Protein Phosphatase (PHLPP) 2 as an important target of MARCH1. Mechanistically, MARCH1 interacted with PHLPP2 and promoted PHLPP2 ubiquitination. Lastly, MARCH1 knockdown suppressed OSCC tumorigenicity in vivo and increased PHLPP2 protein level.

CONCLUSION

Our study uncovered a function of MARCH1 in OSCC and identified PHLPP2 as an important target of MARCH1 to modulate OSCC cell proliferation and apoptosis.

Combination of mTOR inhibitor PP242 and AMPK activator metformin exerts enhanced inhibitory effects on colorectal carcinoma cells in vitro by blocking multiple kinase pathways

The second-generation mammalian target of rapamycin (mTOR) inhibitor PP242 has demonstrated limited success in some rapamycin-insensitive tumours. We examined the therapeutic potential of combining PP242 with adenosine 50- monophosphate-activated protein kinase (AMPK) activator metformin, using a panel of colorectal carcinoma (CRC) cell lines. We found that the PP242 and metformin combination enhanced the suppression of CRC cell proliferation, colony formation, and cancer cell apoptosis induction. The effect of this combination was observed on AMPK phosphorylation. Western blotting showed that PP242 inhibited mTORC1 activation, as indicated by the reduced expression of its major substrate p-S6K1 and the partially reduced phosphorylation of eIF4E-binding protein 1 (4E-BP1). The inhibition of mTORC2-mediated AKT phosphorylation at Ser 473 (AKT Ser473) was transient and occurred in the first few hours of PP242 treatment; metformin exposure decreased the PP242 activity, counteracting AKT activation. We further demonstrated that this was related to direct AMPK-mediated phosphorylation of IRS-1 at Ser789. Thus, the combination of PP242 and metformin completely blocked the activity of both mTORC1 and mTORC2 kinase. This study suggests that this combination could be a more effective strategy for the treatment of CRC.

Bioactive Components and Potential Mechanism Prediction of Kui Jie Kang against Ulcerative Colitis via Systematic Pharmacology and UPLC-QE-MS Analysis

Kui Jie Kang (KJK)—a traditional Chinese medicine—has demonstrated clinical therapeutic efficacy against ulcerative colitis (UC). However, the active compounds and their underlying mechanisms have not yet been fully characterized. Therefore, the current study sought to identify the volatile compounds in KJK responsible for eliciting the therapeutic effect against UC, while also analyzing key targets and potential mechanisms. To this end, systematic network pharmacology analysis was employed to obtain UC targets by using GeneCards, DisGeNET, OMIM, among others. A total of 145 candidate ingredients, 412 potential targets of KJK (12 herbs), and 1605 UC targets were identified. Of these KJK and UC targets, 205 intersected and further identified AKT1, JUN, MAPK, ESR, and TNF as the core targets and the PI3K/AKT signaling pathway as the top enriched pathway. Moreover, molecular docking and ultra-performance liquid chromatography Q Exactive-mass spectrometry analysis identified quercetin, kaempferol, luteolin, wogonin, and nobiletin as the core effective compounds of KJK. In vivo murine studies revealed that KJK exposure increases the body weight and colon length, while reducing colonic epithelial injury, and the expression of inflammatory factors in colitis tissues such as TNF-α, IL-6, and IL-1β. Furthermore, KJK treatment downregulates the expression of pi3k and akt genes, as well as p-PI3K/PI3K and p-AKT/AKT proteins. Collectively, these findings describe the therapeutic effects and mechanisms of KJK in UC and highlight KJK as a potentially valuable therapeutic option for UC via modulation of the PI3K/AKT signaling pathway, thus providing a theoretical reference for the broader application of KJK in the clinical management of UC.

Protective Effect of Hedyotis diffusa Willd. Ethanol Extract on Isoniazid-Induced Liver Injury in the Zebrafish Model

Objective

Methods

Results

Conclusion

The role of the PI3K/AKT signalling pathway in the corneal epithelium: recent updates

Phosphatidylinositol 3 kinase (PI3K)/AKT (also called protein kinase B, PKB) signalling regulates various cellular processes, such as apoptosis, cell proliferation, the cell cycle, protein synthesis, glucose metabolism, and telomere activity. Corneal epithelial cells (CECs) are the outermost cells of the cornea; they maintain good optical performance and act as a physical and immune barrier. Various growth factors, including epidermal growth factor receptor (EGFR) ligands, insulin-like growth factor 1 (IGF1), neurokinin 1 (NK-1), and insulin activate the PI3K/AKT signalling pathway by binding their receptors and promote antiapoptotic, anti-inflammatory, proliferative, and migratory functions and wound healing in the corneal epithelium (CE). Reactive oxygen species (ROS) regulate apoptosis and inflammation in CECs in a concentration-dependent manner. Extreme environments induce excess ROS accumulation, inhibit PI3K/AKT, and cause apoptosis and inflammation in CECs. However, at low or moderate levels, ROS activate PI3K/AKT signalling, inhibiting apoptosis and stimulating proliferation of healthy CECs. Diabetes-associated hyperglycaemia directly inhibit PI3K/AKT signalling by increasing ROS and endoplasmic reticulum (ER) stress levels or suppressing the expression of growth factors receptors and cause diabetic keratopathy (DK) in CECs. Similarly, hyperosmolarity and ROS accumulation suppress PI3K/AKT signalling in dry eye disease (DED). However, significant overactivation of the PI3K/AKT signalling pathway, which mediates inflammation in CECs, is observed in both infectious and noninfectious keratitis. Overall, upon activation by growth factors and NK-1, PI3K/AKT signalling promotes the proliferation, migration, and anti-apoptosis of CECs, and these processes can be regulated by ROS in a concentration-dependent manner. Moreover, PI3K/AKT signalling pathway is inhibited in CECs from individuals with DK and DED, but is overactivated by keratitis.

Coeloglossum viride Var. Bracteatum Extract Attenuates MPTP-Induced Neurotoxicity in vivo by Restoring BDNF-TrkB and FGF2-Akt Signaling Axis and Inhibiting RIP1-Driven Inflammation

The tuber of Coeloglossum viride var. bracteatum is a Tibetan medicine that has been used for generations as a tonic for Yang and Qi, tranquilizing, to enhance intelligence and to promote longevity. We have previously characterized the constituents of Coeloglossum viride var. bracteatum extract (CE) and investigated its anti-Alzheimer's disease (AD) effect in mice models. However, the exact role of CE in Parkinson's disease (PD), especially the neurotrophic and inflammatory pathways regulated by CE, remains unknown. In this study, we investigated the anti-PD effects of CE in an MPTP-induced acute mouse model and its underlying mechanisms, focusing on BDNF, FGF2 and their mediated signaling pathways and RIP1-driven inflammatory signaling axis. Pole test and traction test were performed for behavioral analysis. RT-PCR, IHC and Western blotting were performed to assay the mRNA, tissues, and protein, respectively. We found that CE improved dyskinesia in MPTP-intoxicated mice, which was confirmed by the pole test and traction test. Also, oxidative stress and astrocyte activation and inflammation were alleviated. MPTP-intoxication disrupted the levels of BDNF, FGF2 and their mediated signaling pathways, triggered elevation of pro-inflammatory factors such as TNF-α, IL-1β, and IL-6, and activated RIP1-driven inflammatory axis. However, CE restored the levels of BDNF, FGF2 and TrkB/Akt signaling pathways while inhibiting the RIP1-driven inflammatory signaling axis, thereby inhibiting apoptosis, preventing loss of nigrostriatal neurons, and maintaining cellular homeostasis. Thus, CE is a promising agent for the treatment of PD.

Crosstalk between PI3K/AKT/mTOR and WNT/β-Catenin signaling in GBM - Could combination therapy checkmate the collusion?

Glioblastoma multiforme is one of the calamitous primary glial brain tumors with extensive heterogeneity at cellular and molecular levels. While maximal surgical resection trailed by radio and chemotherapy employing temozolomide remains the gold-standard treatment for malignant glioma patients, the overall prognosis remains dismal and there exists an unmet need for effective therapeutic strategies. In this context, we hypothesize that proper understanding of signaling pathways responsible for glioblastoma multiforme proliferation would be the first trump card while searching for novel targeted therapies. Among the pathways aberrantly activated, PI3K/AKT/mTOR is the most significant pathway, that is clinically implicated in malignancies such as high-grade glioma. Further, the WNT/β-Catenin cascade is well-implicated in several malignancies, while its role in regulating glioma pathogenesis has only emerged recently. Nevertheless, oncogenic activation of both these pathways is a frequent event in malignant glioma that facilitates tumor proliferation, stemness and chemo-resistance. Recently, it has been reported that the cross-talk of PI3K/AKT/mTOR pathway with multiple signaling pathways could promote glioma progression and reduce the sensitivity of glioma cells to the standard therapy. However, very few studies had focused on the relationship between PI3K/AKT/mTOR and WNT/β-Catenin pathways in glioblastoma multiforme. Interestingly, in homeostatic and pathologic circumstances, both these pathways depict fine modulation and are connected at multiple levels by upstream and downstream effectors. Thus, gaining deep insights on the collusion between these pathways would help in discovering unique therapeutic targets for glioblastoma multiforme management. Hence, the current review aims to address, "the importance of inter-play between PI3K/AKT/mTOR and WNT/β-Catenin pathways", and put forward, "the possibility of combinatorially targeting them", for glioblastoma multiforme treatment enhancement.

Recent Advances in Chitosan and its Derivatives in Cancer Treatment

Cancer has become a main public health issue globally. The conventional treatment measures for cancer include surgery, radiotherapy and chemotherapy. Among the various available treatment measures, chemotherapy is still one of the most important treatments for most cancer patients. However, chemotherapy for most cancers still faces many problems associated with a lot of adverse effects, which limit its therapeutic potency, low survival quality and discount cancer prognosis. In order to decrease these side effects and improve treatment effectiveness and patient’s compliance, more targeted treatments are needed. Sustainable and controlled deliveries of drugs with controllable toxicities are expected to address these hurdles. Chitosan is the second most abundant natural polysaccharide, which has excellent biocompatibility and notable antitumor activity. Its biodegradability, biocompatibility, biodistribution, nontoxicity and immunogenicity free have made chitosan become a widely used polymer in the pharmacology, especially in oncotherapy. Here, we make a brief review of the main achievements in chitosan and its derivatives in pharmacology with a special focus on their agents delivery applications, immunomodulation, signal pathway modulation and antitumor activity to highlight their role in cancer treatment. Despite a large number of successful studies, the commercialization of chitosan copolymers is still a big challenge. The further development of polymerization technology may satisfy the unmet medical needs.

mTOR signaling as a molecular target for the alleviation of Alzheimer's disease pathogenesis

Mechanistic/mammalian target of rapamycin (mTOR) belongs to the phosphatidylinositol kinase-related kinase (PIKK) family. mTOR signaling is required for the commencement of essential cell functions including autophagy. mTOR primarily governs cell growth in response to favourable nutrients and other growth stimuli. However, it also influences aging and other aspects of nutrient-related physiology such as protein synthesis, ribosome biogenesis, and cell proliferation in adults with very limited growth. The major processes for survival such as synaptic plasticity, memory storage and neuronal recovery involve a significant mTOR activity. mTOR dysregulation is becoming a prevalent motif in a variety of human diseases, including cancer, neurological disorders, and other metabolic syndromes. The use of rapamycin to prolong life in different animal models may be attributable to the multiple roles played by mTOR signaling in various processes involved in ageing, protein translation, autophagy, stem cell pool turnover, inflammation, and cellular senescence. mTOR activity was found to be altered in AD brains and rodent models, supporting the notion that aberrant mTOR activity is one of the key events contributing to the onset and progression of AD hallmarks This review assesses the molecular association between the mTOR signaling pathway and pathogenesis of Alzheimer's disease. The research data supporting this theme are also reviewed.

Targeting KRAS in Non-Small Cell Lung Cancer

Kirsten Rat Sarcoma viral oncogene homolog (KRAS) is the most frequently altered oncogene in Non-Small Cell Lung Cancer (NSCLC). KRAS mutant tumors constitute a heterogeneous group of diseases, different from other oncogene-derived tumors in terms of biology and response to treatment, which hinders the development of effective drugs against KRAS. Therefore, for decades, despite enormous efforts invested in the development of drugs aimed at inhibiting KRAS or its signaling pathways, KRAS was considered to be undruggable. Recently, the discovery of a new pocket under the effector binding switch II region of KRAS G12C has allowed the development of direct KRAS inhibitors such as sotorasib, the first FDA-approved drug targeting KRAS G12C, or adagrasib, initiating a new exciting era. However, treatment with targeted KRAS G12C inhibitors also leads to resistance, and understanding the possible mechanisms of resistance and which drugs could be useful to overcome it is key. Among others, KRAS G12C (ON) tricomplex inhibitors and different combination therapy strategies are being analyzed in clinical trials. Another area of interest is the potential role of co-mutations in treatment selection, particularly immunotherapy. The best first-line strategy remains to be determined and, due to the heterogeneity of KRAS, is likely to be based on combination therapies.

GqPCR-stimulated dephosphorylation of AKT is induced by an IGBP1-mediated PP2A switch

BACKGROUND

G protein-coupled receptors (GPCRs) usually regulate cellular processes via activation of intracellular signaling pathways. However, we have previously shown that in several cell lines, GqPCRs induce immediate inactivation of the AKT pathway, which leads to JNK-dependent apoptosis. This apoptosis-inducing AKT inactivation is essential for physiological functions of several GqPCRs, including those for PGF2α and GnRH.

METHODS

Here we used kinase activity assays of PI3K and followed phosphorylation state of proteins using specific antibodies. In addition, we used coimmunoprecipitation and proximity ligation assays to follow protein-protein interactions. Apoptosis was detected by TUNEL assay and PARP1 cleavage.

RESULTS

We identified the mechanism that allows the unique stimulated inactivation of AKT and show that the main regulator of this process is the phosphatase PP2A, operating with the non-canonical regulatory subunit IGBP1. In resting cells, an IGBP1-PP2Ac dimer binds to PI3K, dephosphorylates the inhibitory pSer608-p85 of PI3K and thus maintains its high basal activity. Upon GqPCR activation, the PP2Ac-IGBP1 dimer detaches from PI3K and thus allows the inhibitory dephosphorylation. At this stage, the free PP2Ac together with IGBP1 and PP2Aa binds to AKT, causing its dephosphorylation and inactivation.

CONCLUSION

Our results show a stimulated shift of PP2Ac from PI3K to AKT termed "PP2A switch" that represses the PI3K/AKT pathway, providing a unique mechanism of GPCR-stimulated dephosphorylation. Video Abstract.