Phosphoinositide-specific phospholipase Cγ1 inhibition induces autophagy in human colon cancer and hepatocellular carcinoma cells

Qi Lang formula relieves constipation via targeting SCF/c-kit signaling pathway: An integrated study of network pharmacology and experimental validation

Background

Constipation is one of the chronic gastrointestinal functional diseases that affects the quality of life. While Qi Lang Formula (QLF) has demonstrated effectiveness in alleviating constipation symptoms, its precise mechanism remains elusive.

Methods

QLF was analyzed using UPLC-MS/MS. Targets for QLF were collected from SwissADME, Herb, ITCM databases, and constipation-related targets from scRNA-seq and Genecards databases. Overlapping targets suggested potential QLF therapy targets for constipation. Enrichment analysis used the KOBAS database. A "drug-ingredient-target" network was constructed with Cytoscape, and AutoDock verified active ingredient binding. H&E staining assessed colonic mucosa changes, TEM examined ICC structural changes. ELISA measured neurotransmitter levels, and Western blot verified QLF's effect on target proteins. ICC proliferation was observed through immunofluorescence.

Results

We identified 89 targets of QLF associated with ICC-related constipation, with c-Kit emerging as the pivotal target. Molecular docking studies revealed that Atractylenolide Ⅲ, Apigenin, Formononetin, Isorhamnetin, Naringenin, and Ononin exhibited strong binding affinities for the c-Kit structural domain. QLF significantly enhanced first stool passage time, fecal frequency, fecal moisture content, and intestinal propulsion rate. Further analysis unveiled that QLF not only restored neurotransmitter levels but also mitigated colon muscular fiber ruptures. ICC ultrastructure exhibited partial recovery, while Western blot confirmed upregulated c-Kit expression and downstream targets. Immunofluorescence results indicated ICC proliferation post QLF treatment in rat colon.

Conclusion

Our findings suggest that QLF may promote ICC proliferation by targeting SCF/c-Kit and its downstream signaling pathway, thereby regulating intestinal motility.

Impaired autophagy contributes to the aggravated deterioration of osteoarthritis articular cartilage by peroxisome proliferator-activated receptor α deficiency, associated with decreased ERK and Akt activation

BACKGROUND

Although the chondroprotection of peroxisome proliferator-activated receptor α (PPARα) activation against osteoarthritis (OA) has been revealed, the regulatory mechanism of PPARα deficiency to aggravate osteoarthritic cartilage deterioration remains unclear. Here, we aimed to investigate whether and how autophagy is involved in OA pathological progression.

METHODS

Model of experimental OA was established using destabilization of the medial meniscus in PPARα-KO 129S4/SvJae male mice, followed by histopathological detection of articular cartilage and immunohistochemistry detection of extracellular matrix (ECM) or autophagy-related signal molecules. Meanwhile, human OA chondrocytes obtained from total knee replacement surgery patients with OA were cultured with the pretreatment of IL-1β, followed with the treatment of PPARα agonist WY14643 and the detection of related signal molecules.

RESULTS

PPARα deficiency aggravated cartilage damage with decreased LC3B level in combination with an increase in P62 level, accompanied with reduced p-Akt and p-ERK levels in PPARα-KO mouse model of experimental OA. On the contrary, PPARα activation by WY14643 promoted ECM synthesis in IL-1β-treated human OA chondrocytes, accompanied with increased LC3B-II/I ratio and Beclin 1 level and decreased P62 and Bcl2 levels. Meanwhile, it was observed that activated ERK and Akt by PPARα activation contributed to the enhancement of autophagy and ECM synthesis in human OA chondrocytes.

CONCLUSIONS

Impaired autophagy contributed to the aggravated deterioration of osteoarthritis articular cartilage by PPARα deficiency associated with the suppression of ERK and Akt, with an implication that triggering PPARα activation ought to be a potential promising therapeutic target for OA therapy.

Study on the Mechanism of MicroRNA551b-5p in Severe Acute Pancreatitis Capillary Leakage Syndrome

Objective

This study focused on investigating the effects of microRNA551b-5p (miR-551b-5p) on severe acute pancreatitis.

Methods

Initially, quantitative real-time polymerase chain reaction (qPCR) is employed to determine the expression of miR-551b-5p in differentiated human umbilical vein endothelial cells (HUVECs). Further, the effects of aberrantly expressed miR-551b-5p in HUVECs Transwell assay. The expressions of proteins associated with severe acute pancreatitis capillary leakage syndrome are determined by Western blot, FITC-phalloidin, and immunofluorescence stainings. Finally, the correlative factor and the target genes of miR-551b-5p, as well as their contributions, are assessed.

Results

We observed that overexpression of miR-551b-5p distinctly promoted the expression of EGFR, AKT3, and AQP5, while it suppressed the expression of JAM3, AQP1, and occludin. Functionally, the cytoskeleton of the miR-551b-5p overexpression was relatively loose with apparent vacuoles, and overexpression of miR-551b-5p increased the permeability of HUVECs.

Conclusion

miR-551b-5p overexpression promoted changes in vascular endothelial permeability via upregulation of the EGFR/AKT3 pathway and downregulation of occludin and JAM3.

Suppressing phosphoinositide-specific phospholipases Cγ1 promotes mineralization of osteoarthritic subchondral bone osteoblasts via increasing autophagy, thereby ameliorating articular cartilage degeneration

INTRODUCTION

Phosphoinositide-specific phospholipases C-γ1 (PLC-γ1) signaling has been shown to modulate osteoarthritis (OA) chondrocyte metabolism. However, the role of PLC-γ1 in OA osteoblasts remains unclear. Herein, whether and how PLC-γ1 was involved in mineralization in OA subchondral bone osteoblasts were investigated.

METHODS

Primary non-OA and OA osteoblasts of human and rat isolated from the subchondral bone or the calvaria were cultured in vitro, as well as mouse pre-osteoblastic cell line MC3T3-E1 cells. Rat knee OA model was induced by anterior cruciate ligament transection (ACLT), in which bone canal was carried out from the surface of lateral epicondyle of femur using micro-electric drill. Morphological characteristics of subchondral bone structure and articular cartilage were assessed using CT, micro-CT, and Safranin O/Fast green staining, respectively. Mineralization was measured by alizarin red staining. The expression and production of genes involved in osteoblastic phenotype and mineralization were evaluated by qPCR, western blotting, and immunohistochemistry assays, respectively. The inhibitions were performed using inhibitors and ShRNAs.

RESULTS

The decreased relative bone density and thickness in the early stage of OA and the increased one in the late stage of OA were observed in subchondral bone of ACLT-rat model. Decreased ALP and OCN levels and absorbance values of ARS content were observed in in vitro osteoblasts isolated from 2 w post-ACLT rat model, as well as IL-1β-treated (for maintaining and mimicking inflammatory status) human OA and rat osteoblasts. Decreased Atg7 level and LC3BII/I ratio in combination with an increase in the P62 level, was concomitant with decreased ALP and OCN mRNA levels and absorbance values of ARS content in OA or IL-1β-treated osteoblasts. Specific inhibition of PLC-γ1 by ShRNAs or inhibitor (U73122) elevated ALP and OCN mRNA levels and absorbance values of ARS content accompanied with increased Atg7 level and LC3BII/I ratio in combination with a decrease in the P62 level in OA osteoblasts. Furthermore, the promoting effect of PLC-γ1 inhibition on ALP and OCN mRNA levels and absorbance values of ARS content was reversed by endoplasmic reticulum (ER) stress activator HA15, as well as autophagic inhibitors CQ and 3MA. Injection with PLC-γ1 inhibitor U73122 from the surface of lateral epicondyle of femur reduced aberrant subchondral bone formation and attenuated articular cartilage degeneration in ACLT-rat.

CONCLUSION

Aberrant changes of OA subchondral bone structure were concomitant with altered osteoblastic phenotype and mineralization. Impaired autophagy contributed to decreased osteoblastic mineralization in the early stage of OA. PLC-γ1 inhibition promoted osteoblastic mineralization through increasing autophagy in OA osteoblasts, which was partially attributed to suppression of ER stress. Targeting PLC-γ1 in subchondral bone osteoblasts could be more efficacious for OA therapy through treating the bone and cartilage at the same time. In summary, we hypothesize that suppressing PLCγ1 promotes mineralization of osteoarthritic subchondral bone osteoblasts via increasing autophagy, thereby ameliorating articular cartilage degeneration.

The role of PDGFRA as a therapeutic target in young colorectal cancer patients

Background

Young patients with colorectal cancer (CRC) exhibit poor prognoses compared to older patients due to the difficulty in early diagnosis and treatment. However, the underlying molecular characteristics are still unclear.

Methods

We conducted a comprehensive analysis of 49 CRC patients without hereditary CRC using the whole-exome and RNA sequencing with tumor and matched normal samples. A total of 594 TCGA samples and 4 patient-derived cells were utilized for validation.

Results

Consensus molecular subtype 4 (CMS4) (53.85%) and CMS2 (38.46%) were enriched in the young (≤ 40 years) and old (> 60 years) age groups, respectively. A CMS4-associated gene, platelet-derived growth factor receptor α (PDGFRA), was significantly upregulated in young patients with CRC (FC = 3.21, p = 0.0001) and was negatively correlated with age (p = 0.0001, R = − 0.526). Moreover, PDGFRA showed a positive co-expression with metastasis-related genes in young CRC patients. In vitro validation confirmed that young patient-derived cells (PDCs) showed an enriched expression of PDGFRA compared to old PDCs and a reduced proliferation rate by knockdown of PDGFRA. Furthermore, young CRC patients were more sensitive to regorafenib, a PDGFRA-targeting drug, than old CRC patients.

Conclusions

Our study suggests that CRC in young patients is associated with CMS4 and PDGFRA. In addition, PDGFRA may serve potential of novel therapeutic strategies and represent a predictive biomarker of response to regorafenib for young CRC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-03088-7.

Adenine Inhibits the Invasive Potential of DLD-1 Human Colorectal Cancer Cell via the AMPK/FAK Axis

Tumor metastasis is a major cause of death of patients with colorectal cancer (CRC). Our previous findings show that adenine has antiproliferation activity against tumor cells. However, whether adenine reduces the invasiveness of DLD-1 and SW480 CRC cells has not been thoroughly explored. In this study, we aimed to explore the effects of adenine on the invasion potential of DLD-1 cells. Our findings showed that adenine at concentrations of ≤200 μM did not influence the cell viability of DLD-1 and SW480 CRC cells. By contrast, adenine reduced the migratory potential of the CRC cells. Moreover, it decreased the invasion capacity of the CRC cells in a dose-dependent manner. We further observed that adenine downregulated the protein levels of tissue plasminogen activator, matrix metalloproteinase-9, Snail, TWIST, and vimentin, but upregulated the tissue inhibitor of metalloproteinase-1 expression in DLD-1 cells. Adenine decreased the integrin αV level and reduced the activation of integrin-associated signaling components, including focal adhesion kinase (FAK), paxillin, and Src in DLD-1 cells. Further observations showed that adenine induced AMP-activated protein kinase (AMPK) activation and inhibited mTOR phosphorylation in DLD-1 cells. The knockdown of AMPK restored the reduced integrin αV level and FAK/paxillin/Src signaling inhibited by adenine in DLD-1 cells. Collectively, these findings reveal that adenine reduces the invasion potential of DLD-1 cells through the AMPK/integrin/FAK axis, suggesting that adenine may have anti-metastatic potential in CRC cells.

Autophagy is a double-edged sword in the therapy of colorectal cancer

Colorectal cancer is one of the leading causes of cancer-associated mortality worldwide. The limitations of colorectal cancer treatment include various types of multidrug resistance and the contingent damage to neighboring normal cells caused by chemotherapy. Macroautophagy/autophagy and apoptosis are essential mechanisms involved in cancer cell regulation of chemotherapy. Autophagy can either cause cancer cell death or promote tumor survival during colorectal cancer. Given that autophagy is involved in chemotherapy of colorectal cancer, an improved insight into the potential interactions between apoptosis and autophagy is crucial. The present review aimed to summarize the involvement of autophagy in the regulation of colorectal cancer and its association with chemotherapy. Furthermore, the role of natural product extraction, novel chemicals and small molecules, as well as radiation, which induce autophagy in colorectal cancer cells, were reviewed. Finally, the present review aimed to provide an outlook for the regulation of autophagy as a novel approach to the treatment of cancer, particularly chemotherapy-resistant colorectal cancer.

PLCγ1 inhibition combined with inhibition of apoptosis and necroptosis increases cartilage matrix synthesis in IL-1β-treated rat chondrocytes

Osteoarthritis (OA) is an age‐related, chronic degenerative disease. With the increasing median age of the population, this disease has become an important public health problem. New, disease‐modifying therapies are needed. A potential novel molecular target is phospholipase Cγ1 (PLCγ1), a critical enzyme with important functions including calcium signaling regulation and cell proliferation. In rat chondrocytes treated with IL‐1β (20 ng·mL⁻¹ for 36 h), inhibition of PLCγ1 with U73122 (2 μm for 12 h) increased levels and expression of the cartilage matrix components Collagen2 and Aggrecan. This beneficial effect of PLCγ1 inhibition was counteracted by increased chondrocyte apoptosis and necroptosis, increased cell death, and increase levels of ROS, all potentially negative for OA. Combined treatment of IL‐1β + U73122‐treated chondrocytes with inhibitors of apoptosis (Z‐VAD, 10 μm) and necroptosis (Nec‐1, 30 μm) enhanced the increases in levels and expression of Collagen2 and Aggrecan, and prevented the increases in cell death and ROS levels. These results suggest that PLCγ1 inhibition may be a viable approach for an OA therapy, if combined with targeted inhibition of chondrocyte apoptosis and necroptosis.

PLCγ1 inhibition-driven autophagy of IL-1β-treated chondrocyte confers cartilage protection against osteoarthritis, involving AMPK, Erk and Akt

Previous studies identified the involvement of phosphoinositide‐specific phospholipase C (PLC) γ1 in some events of chondrocytes. This study aims to investigate whether and how PLCγ1 modulates autophagy to execute its role in osteoarthritis (OA) progression. Rat normal or human OA chondrocytes were pretreated with IL‐1β for mimicking or sustaining OA pathological condition. Using Western blotting, immunoprecipitation, qPCR, immunofluorescence and Dimethylmethylene blue assays, and ELISA and transmission electron microscope techniques, we found that PLCγ1 inhibitor U73122 enhanced Collagen II, Aggrecan and GAG levels, accompanied with increased LC3B‐II/I ratio and decreased P62 expression level, whereas autophagy inhibitor Chloroquine partially diminished its effect. Meanwhile, U73122 dissociated Beclin1 from Beclin1‐IP3R‐Bcl‐2 complex and blocked mTOR/ULK1 axis, in which the crosstalk between PLCγ1, AMPK, Erk and Akt were involved. Additionally, by haematoxylin and eosin, Safranin O/Fast green, and immunohistochemistry staining, we observed that intra‐articular injection of Ad‐shPLCγ1‐1/2 significantly enhanced Collagen and Aggrecan levels, accompanied with increased LC3B and decreased P62 levels in a rat OA model induced by anterior cruciate ligament transection and medial meniscus resection. Consequently, PLCγ1 inhibition‐driven autophagy conferred cartilage protection against OA through promoting ECM synthesis in OA chondrocytes in vivo and in vitro, involving the crosstalk between PLCγ1, AMPK, Erk and Akt.

The Role of Calcium Signaling in Regulation of Epithelial-Mesenchymal Transition

Despite substantial advances in the field of cancer therapeutics, metastasis is a significant challenge for a favorable clinical outcome. Epithelial to mesenchymal transition (EMT) is a process of acquiring increased motility, invasiveness, and therapeutic resistance by cancer cells for their sustained growth and survival. A plethora of intrinsic mechanisms and extrinsic microenvironmental factors drive the process of cancer metastasis. Calcium (Ca2+) signaling plays a critical role in dictating the adaptive metastatic cell behavior comprising of cell migration, invasion, angiogenesis, and intravasation. By modulating EMT, Ca2+ signaling can regulate the complexity and dynamics of events leading to metastasis. This review summarizes the role of Ca2+ signal remodeling in the regulation of EMT and metastasis in cancer.

Suppressing PLCγ1 enhances osteogenic and chondrogenic potential of BMSCs

Phosphatidylcholine-specific phospholipase Cγ1 (PLCγ1) is involved in regulating cell metabolism. However, little is known how PLCγ1 directs BMSC differentiation. Here, we investigated the role of PLCγ1 in rat BMSC differentiation into osteoblasts and chondrocytes. The results of Alizarin red and Alcian blue staining showed that PLCγ1 inhibitor U73122 significantly enhanced the mineralization capacity and proteoglycan deposition of BMSCs. The results of qPCR technique and Western blot analysis showed that long-term treatment of U73122 enhanced COL1A1 and OPG mRNA levels and Collagen 1A1, BMP2, and p-Smad1/5/9 protein levels and that short-term treatment of U73122 enhanced COL2A1 and SOX9 mRNA levels and Collagen 2, SOX9, Aggrecan, TGF-β3, and p-Smad2/3 protein levels. Decreased p-mTOR and p-P38 contributed to enhanced osteogenic potentials of BMSCs and increased p-P38 contributed to enhanced chondrogenic potentials of BMSCs. The scaffold transplantation with U73122+BMSC was more efficacious than BMSC alone for osteochondral defect repair in a rat model. Therefore, suppressing PLCγ1 could improve the capacity to effectively use BMSCs for cell therapy of osteochondral defect.

Phosphoinositide specific phospholipase Cγ1 inhibition-driven autophagy caused cell death in human lung adenocarcinoma A549 cells in vivo and in vitro

Our previous studies indicated that phosphoinositide specific phospholipase Cγ1 (PLCγ1) was involved in autophagy induction in colon and hepatic carcinoma cells. However, whether and how PLCγ1 regulation in human lung adenocarcinoma is linked to autophagy remains unclear. Here, we assessed the protein expression of PLCγ1 in human lung adenocarcinoma tissue using immunohistochemistry assay and the relationship between PLCG1 and autophagy in The Cancer Genome Atlas Network (TCGA) using Spearman correlation analysis and GSEA software. Furthermore, the interaction between PLCγ1 and autophagy-related signal molecules was investigated in human lung adenocarcinoma A549 cells treated with different inhibitors or transduction with lentivirus-mediated PLCγ1 gene short-hairpin RNA (shRNA) vectors using MTT, clonogenicity, Transwell migration, RT-PCR, Caspase-3, mitochondrial transmembrane potential, and western blotting assays, as well as transmission electron microscope technique. Additionally, the effect of shRNA/PLCγ1 alone or combined with autophagic activator Lithium Chloride (LiCl) on tumor growth and metastasis was measured using immunohistochemistry and assays in A549 xenograft nude mouse model. The results showed that increased PLCγ1 expression occurred frequently in human lung adenocarcinoma tissue with higher grades of T in TNM staging classification. PLCγ1 significantly enriched in autophagic process and regulation, which negatively regulating autophagy was enriched in higher expression of PLCγ1. PLCγ1 inhibition partially reduced cell proliferation and migration of A549 cells, with an increased autophagic flux involving alterations of AMPKα, mTOR, and ERK levels. However, PLCγ1 inhibition-driven autophagy led to cell death without depending on Caspase-3 and RIP1. Additionally, the abrogation of PLCγ1 signaling by shRNA and combination with autophagic activator LiCl could efficaciously suppress tumor growth and metastasis in A549 xenograft nude mice, in combination with a decrease in P62 level. These findings collectively suggest that reduction of cell proliferation and migration by PLCγ1 inhibition could be partially attributed to PLCγ1 inhibition-driven autophagic cell death (ACD). It highlights the potential role of a combination between targeting PLCγ1 and autophagy pathway in anti-tumor therapy, which may be an efficacious new strategy to overcome the autophagy addition of tumor and acquired resistance to current therapy.

IL-1β receptor antagonist (IL-1Ra) combined with autophagy inducer (TAT-Beclin1) is an effective alternative for attenuating extracellular matrix degradation in rat and human osteoarthritis chondrocytes

Background

Autophagy induction is an effective approach for OA therapy. IL-1β is one of the major inflammatory cytokines linked to OA pathological progression, and its receptor blockade interrupts OA cartilage destruction. The objective of this study was to decipher the link between autophagy and regulatory mechanism of IL-1β and to investigate the effect of IL-1β receptor blockade by IL-1 receptor antagonist (IL-1Ra) combined with or without an autophagy inducer (TAT-Beclin1) on extracellular matrix (ECM) in OA chondrocytes in vitro and in vivo.

Methods

IL-1β-treated rat and human OA chondrocytes were cultured in response to IL-1Ra. The expression and distribution of signal molecules regulating ECM synthesis and autophagy were investigated via western blotting, immunoprecipitation, real-time PCR, immunofluorescence, and transmission electron microscope technique. Furthermore, after intra-articular injection of IL-1Ra, TAT-Beclin1, and a combination of both in a rat OA model established by anterior cruciate ligament transection and medial meniscus resection, the morphological changes of cartilage and related signal molecule expression levels were monitored using H.E., Safranin O-Fast green, and immunohistochemistry staining.

Results

Reduced autophagy by IL-1β contributed to ECM degradation, and blockade of IL-1β by IL-1Ra restored autophagy and attenuated ECM degradation in rat and human OA chondrocytes, as well as in a rat OA model. Akt/mTOR/ULK1, Akt/mTOR/NF-κB, and LC3B deacetylation were involved in autophagy regulated by IL-1β. Intra-articular injection of IL-1Ra combined with TAT-Beclin1 was more effective than IL-1Ra alone.

Conclusions

IL-1Ra restored autophagy and attenuated ECM degradation, with an implication that blocking IL-1β combined with enhancing autophagy might be a potential therapeutic strategy for OA.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1952-5) contains supplementary material, which is available to authorized users.

LKB1 expressed in dendritic cells governs the development and expansion of thymus-derived regulatory T cells

Liver Kinase B1 (LKB1) plays a key role in cellular metabolism by controlling AMPK activation. However, its function in dendritic cell (DC) biology has not been addressed. Here, we find that LKB1 functions as a critical brake on DC immunogenicity, and when lost, leads to reduced mitochondrial fitness and increased maturation, migration, and T cell priming of peripheral DCs. Concurrently, loss of LKB1 in DCs enhances their capacity to promote output of regulatory T cells (Tregs) from the thymus, which dominates the outcome of peripheral immune responses, as suggested by increased resistance to asthma and higher susceptibility to cancer in CD11c^ΔLKB1 mice. Mechanistically, we find that loss of LKB1 specifically primes thymic CD11b⁺ DCs to facilitate thymic Treg development and expansion, which is independent from AMPK signalling, but dependent on mTOR and enhanced phospholipase C β1-driven CD86 expression. Together, our results identify LKB1 as a critical regulator of DC-driven effector T cell and Treg responses both in the periphery and the thymus.

Chondroprotection of PPARα activation by WY14643 via autophagy involving Akt and ERK in LPS-treated mouse chondrocytes and osteoarthritis model

Autophagy maintains cellular homoeostasis. The enhancement of autophagy in chondrocytes could prevent osteoarthritis (OA) progression in articular cartilage. Peroxisome proliferator-activated receptor α (PPARα) activation may also protect articular chondrocytes against cartilage degradation in OA. However, whether the protective effect of activated PPARα is associated with autophagy induction in chondrocytes is not determined. In this study, we investigated the effect of PPARα activation by its agonist, WY14643, on the protein expression level of Aggrecan and ADAMTS5, and the protein expression level of autophagy biomarkers, including LC3B and P62, using Western blotting analysis in isolated mouse chondrocytes pre-treated with lipopolysaccharides (LPS, mimicking OA chondrocytes) with or without the autophagy inhibitor chloroquine diphosphate salt. Furthermore, Akt and ERK phosphorylation was detected in LPS-treated chondrocytes in response to WY14643. In addition, the effect of intra-articularly injected WY14643 on articular cartilage in a mouse OA model established by the destabilization of the medial meniscus was assessed using the Osteoarthritis Research Society International (OARSI) histopathology assessment system, along with the detection of Aggrecan, ADAMTS5, LC3B and P62 protein levels using immunohistochemistry assay. The results indicated that PPARα activation by WY14643 promoted proteoglycan synthesis by autophagy enhancement in OA chondrocytes in vivo and in vitro concomitant with the elevation of Akt and ERK phosphorylation. Therefore, autophagy could contribute to the chondroprotection of PPARα activation by WY14643, with the implication that PPARα activation by WY14643 may be a potential approach for OA therapy.