Piperlongumine Alleviates Mouse Colitis and Colitis-Associated Colorectal Cancer

Repurposing cyclovirobuxine D as a novel inhibitor of colorectal cancer progression via modulating the CCT3/YAP axis

BACKGROUND AND PURPOSE

Colorectal cancer (CRC) ranks second in mortality worldwide and requires effective and affordable remedies. Cyclovirobuxine D (CVB-D) is the main effective component of Huangyangning tablet, an approved traditional patent medicine, which is mainly used for cardiovascular treatment. As a multibioactive natural compound, CVB-D possesses underlying anticancer activities.

EXPERIMENTAL APPROACH

Cell viability and clone-forming ability were determined in human CRC lines. Western blot, immunofluorescence assay, transmission electron microscopy and senescence-associated β-galactosidase (SA-β-Gal) staining were utilized to investigate cell autophagy and senescence. The molecular mechanisms were explored by virtual prediction and experimental validation. Patient-derived xenograft (PDX), dextran sulfate sodium salt (DSS), and azomethane (AOM)/DSS mouse models were employed for in vivo studies.

KEY RESULTS

CVB-D inhibited the growth and development of advanced CRC cells / mice by inducing autophagic and senescent activities through the chaperonin containing TCP1 subunit 3 (CCT3)/yes-associated protein (YAP) axis. CVB-D acted as a promising inhibitor of CCT3 by interacting with its ATP site. In PDX tumours, CVB-D showed potential therapeutic effects by targeting CCT3. Treatment with CVB-D alleviated the mouse model of colitis induced by DSS and attenuated AOM/DSS-induced formation of adenomatous polyps by its action on CCT3.

CONCLUSIONS AND IMPLICATIONS

Our study has provided a scientific basis for the suggestion that CVB-D may be recognized as a prospective drug candidate for the therapy of CRC in patients.

Phase separation of RNF214 promotes the progression of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, and the expression and function of an uncharacterized protein RNF214 in HCC are still unknown. Phase separation has recently been observed to participate in the progression of HCC. In this study, we investigated the expression, function, and phase separation of RNF214 in HCC. We found that RNF214 was highly expressed in HCC and associated with poor prognosis. RNF214 functioned as an oncogene to promote the proliferation, migration, and metastasis of HCC. Mechanically, RNF214 underwent phase separation, and the coiled-coil (CC) domain of RNF214 mediated its phase separation. Furthermore, the CC domain was necessary for the oncogenic function of RNF214 in HCC. Taken together, our data favored that phase separation of RNF214 promoted the progression of HCC. RNF214 may be a potential biomarker and therapeutic target for HCC.

Piperlongumine inhibits antioxidant enzymes, increases ROS levels, induces DNA damage and G2/M cell cycle arrest in breast cell lines

Piperlongumine (PLN) is a biologically active alkaloid/amide derived from Piper longum, with known promising anticancer activity. The aim of this study was to compare the antiproliferative activity of PLN in human breast MCF-7 adenocarcinoma cell line with effects in HB4a normal mammary epithelial non-tumor cell line. The parameters examined were cell growth, viability, reactive oxygen species (ROS) levels and DNA damage, as well as the effects on the modulating targets responsible through regulation of these pathways. PLN increased ROS levels and expression of the SOD1 antioxidant enzyme. PLN inhibited the expression of the antioxidant enzymes catalase, TRx1, and PRx2. The ability of PLN to inhibit antioxidant enzyme expression was associated with the oxidative stress response. PLN induced genotoxicity in both cell lines and upregulated the levels of GADD45A mRNA and p21 protein. The DNA damage response ATR protein was downregulated in both cell lines and contributed to an enhanced PLN genotoxicity. In HB4a cells, Chk1 protein, and mRNA levels were also decreased. In response to elevated ROS levels and DNA damage induction, the cells were arrested at the G2/M phase, probably in an attempt to promote cell survival. Although cell viability was reduced in both cell lines, only HB4a cells underwent apoptotic cell death, whereas other types of cellular death may be involved in MCF-7 cells. Taken together, these data provide insight into the anticancer mechanisms attributed to PLN effects, which acts as an inhibitor of DNA damage response (DDR) proteins and antioxidant enzymes.

Piperlongumine, a Piper longum-derived amide alkaloid, protects mice from ovariectomy-induced osteoporosis by inhibiting osteoclastogenesis via suppression of p38 and JNK signaling

Postmenopausal osteoporosis (PMOP) is a metabolic bone disease that results from overproduction and hyperactivation of osteoclasts caused by insufficient estrogen in women after menopause. Current therapeutic strategies are mainly focused on treating PMOP patients who have already developed severe bone loss or even osteoporotic fractures. Obviously, a better strategy is to prevent PMOP from occurring in the first place. However, such reagents are largely lacking. Piperlongumine (PLM), an amide alkaloid extracted from long pepper Piper longum, exhibits the anti-osteoclastogenic effect in normal bone marrow macrophages (BMMs) and the protective effect against osteolysis induced by titanium particles in mice. This study examined the preventive effect of PLM on PMOP and explored the potential mechanism of this effect using both ovariectomized mice and their primary cells. The result showed that PLM (5 and 10 mg kg-1) administered daily for 6 weeks ameliorated ovariectomy-induced bone loss and osteoclast formation in mice. Further cell experiments showed that PLM directly suppressed osteoclast formation, F-actin ring formation, and osteoclastic resorption pit formation in BMMs derived from osteoporotic mice, but did not obviously affect osteogenic differentiation of bone marrow stromal cells (BMSCs) from these mice. Western blot analysis revealed that PLM attenuated maximal activation of p38 and JNK pathways by RANKL stimulation without affecting acute activation of NF-κB, AKT, and ERK signaling. Furthermore, PLM inhibited expression of key osteoclastogenic transcription factors NFATc1/c-Fos and their target genes (Dcstamp, Atp6v0d2, Acp5, and Oscar). Taken together, our findings suggest that PLM inhibits osteoclast formation and function by suppressing RANKL-induced activation of the p38/JNK-cFos/NFATc1 signaling cascade, thereby preventing ovariectomy-induced osteoporosis in mice. Thus, PLM can potentially be used as an anti-resorption drug or dietary supplement for the prevention of PMOP.

Piperlongumine mitigates LPS-induced inflammation and lung injury via targeting MD2/TLR4

PURPOSE

Acute lung injury (ALI) is a fatal acute inflammatory illness with restricted therapeutic choices clinically. Piperlongumine (PL) is recognized as an alkaloid separated from Piper longum L, which was suggested to exhibit multiple pharmacological activities (e.g., anti-inflammatory activity). However, the effects of PL on LPS-triggered ALI and its anti-inflammatory target remain unclear. This paper intended to assess the roles of PL in LPS-triggered ALI, as well as its underlying mechanism and target.

METHODS

In vivo, ALI was induced by intratracheal injection of LPS to evaluate protective effects of PL and assessed by the changes of histopathological. In vitro, the anti-inflammatory activity and mechanism of PL were investigated by ELISA, RT-qPCR, transcription factor enrichment analysis, Western blotting and Immunofluorescence assay. The binding affinity of PL to MD2 was analyzed using computer docking, surface plasmon resonance, ELISA and immunoprecipitation assay.

RESULTS

It was reported here that PL treatment alleviated LPS-induced pulmonary damage, inflammatory cells infiltration and inflammatory response in mice. In culture cells, PCR array showed that PL significantly inhibited LPS-induced inflammatory cytokines, chemokines, and type I IFNs genetic expression, along with the inhibition of TAK1 and TBK1 pathway. It is noteworthy that PL is capable of straightly binding to MD2 and inhibiting MD2/TLR4 complex formation and TLR4 dimerization.

CONCLUSIONS

As revealed from this study, PL directly binding to MD2 to block cytokines expression by inhibiting the activation of TAK1 and TBK1 pathway, which then exerted its pulmonary protective activity. Accordingly, PL may act as an underlying candidate for treating LPS-triggered ALI.

Genomic analysis quantifies pyroptosis in the immune microenvironment of HBV-related hepatocellular carcinoma

Pyroptosis, a way of pro-inflammatory death, plays a significant part in the tumor microenvironment (TME). A recent study has shown that the hepatitis C virus changes the TME by inducing pyroptosis against hepatocellular carcinoma (HCC). However, compared to TME in hepatitis C virus-infected HCC, the exploration of immune characteristics and response to immunotherapy associated with the pyroptosis phenotype is still insufficient in hepatitis B virus-related HCC (HBV-HCC). Our study constructed pyroptosis-score (PYS) via principal-component analysis (PCA) to unveil the link between pyroptosis and tumor immunity in 369 HBV-HCC patients. Compared with the low-PYS group, subjects with higher PYS were associated with poor prognosis but were more susceptible to anti-PD-L1 treatment. In addition, we found that PYS can serve independently as a prognostic factor for HBV-HCC, making it possible for us to identify specific small molecule drugs with a potential value in inhibiting tumors via targeting pyroptosis. Also, the target genes predicted by the Weighted gene co-expression network analysis (WGCNA) and pharmacophore model were enriched in the HIF-1 signaling pathway and NF-kB transcription factor activity, which were related to the mechanism of inflammation-driven cancer. The PYS is extremely important in predicting prognosis and responses to immunotherapy. New treatment strategies for inflammation-driven cancers may be found by targeting pyroptosis.

Extraction, Chemical Composition, and Protective Effect of Essential Oil from Chimonanthus nitens Oliv. Leaves on Dextran Sodium Sulfate-Induced Colitis in Mice

In this study, the essential oil (EO) was extracted by steam distillation from Chimonanthus nitens Oliv, and the extraction process was optimized by response surface methodology. The optimum process conditions are as follows: extraction time of 4.57 h, soaking time of 1.33 h, and solid-liquid ratio of 1 : 21.4. Under these conditions, the theoretical yield of EO is 1.5624%. The EO compounds were analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 52 chemical components were detected, among which the content of 3-(4,8-dimethylnona-3,7-dienyl)-furan was the highest, accounting for 21.43% of the total peak area. The EO showed good antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2 ${}^{\prime }$ -azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), and reducing power. In this study, we observed the protective effect of EO on ulcerative colitis (UC) induced by dextran sodium sulfate (DSS) in mice. EO effectively delayed weight loss and reduced DAI score. Histological examination also observed a significant reduction in damage in the EO group. The colon length of mice in DSS group was the shortest, and the colon length of mice in EO treatment group was longer than that in model group, but shorter than that in normal group ( $\text{NOR}:8.17\pm 0.39\text{cm};\text{DSS}:5.57\pm 0.93\text{cm};\text{L}-\text{EO}:6.47\pm 0.78\text{cm};\text{M}-\text{EO}:5.98\pm 0.58\text{cm};\text{and}\text{H}-\text{EO}:6.1\pm 0.52\text{cm}$ ). The GSH activity in the L-EO and SASP groups was significantly higher than that in the DSS group ( $P<0.01$ ). SOD activity in L-EO and M-EO groups was also significantly higher than that in DSS treatment group ( $P<0.01$ ). MDA was decreased in the EO treatment groups and the SASP group (L-EO, H-EO, SASP: $P<0.01$ ; M-EO: $P<0.05$ ). MPO of EO treatment group was lower than that of model group (the L-EO group was not significant, M-EO: $P<0.05$ , H-EO: $P<0.05$ ). This study shows that EO can effectively improve the symptoms of colitis.

The promising potential of piperlongumine as an emerging therapeutics for cancer

In spite of the immense advancement in the diagnostic and treatment modalities, cancer continues to be one of the leading causes of mortality across the globe, responsible for the death of around 10 million patients every year. The foremost challenges faced in the treatment of this disease are chemoresistance, adverse effects of the drugs, and the high cost of treatment. Though scientific studies over the past few decades have foreseen and are focusing on the cancer-preventive and therapeutic potential of natural products and their underlying mechanism of action, many more of these agents are not still explored. Piperlongumine (PL), or piplartine, is one such alkaloid isolated from Piper longum Linn. which is shown to be safe and has significant potential in the prevention and therapy of cancer. Numerous shreds of evidence have established the ability of this alkaloid and its analogs and nanoformulations in modulating various complex molecular pathways such as phosphatidylinositol-3-kinase/protein kinase B /mammalian target of rapamycin, nuclear factor kappa-B, Janus kinases/signal transducer and activator of transcription 3, etc. and inhibit different hallmarks of cancer such as cell survival, proliferation, invasion, angiogenesis, epithelial-mesenchymal-transition, metastases, etc. In addition, PL was also shown to inhibit radioresistance and chemoresistance and sensitize the cancer cells to the standard chemotherapeutic agents. Therefore, this compound has high potential as a drug candidate for the prevention and treatment of different cancers. The current review briefly reiterates the anti-cancer properties of PL against different types of cancer, which permits further investigation by conducting clinical studies.