Alterations in Herbage Yield, Antioxidant Activities, Phytochemical Contents, and Bioactive Compounds of Sabah Snake Grass (Clinacanthus Nutans L.) with Regards to Harvesting Age and Harvesting Frequency

Synergistic effects of combined cisplatin and Clinacanthus nutans extract on triple negative breast cancer cells

Objective

Triple negative breast cancer (TNBC) is the most invasive breast cancer subtype enriched with cancer stem cells. TNBCs do not express estrogen, progesterone, or human epidermal growth factor receptor 2 (HER2) receptors, making them difficult to be targeted by existing chemotherapy treatments. In this study, we attempted to identify the effects of combined cisplatin and Clinacanthus nutans treatment on MDA-MD-231 and MDA-MB-468 breast cancer cells, which represent TNBC subtypes.

Methods

The phytochemical fingerprint of C. nutans ethanolic leaf extract was evaluated by LC-MS/MS analysis. We investigated the effects of cisplatin (0-15.23 μg/mL), C. nutans (0-50 μg/mL), and a combination of cisplatin (3.05 μg/mL) and C. nutans (0-50 μg/mL), on cell viability, proliferation, apoptosis, invasion, mRNA expression in cancer stem cells (CD49f, KLF4), and differentiation markers (TUBA1A, KRT18) in TNBC cells. In addition, we also studied the interaction between cisplatin and C. nutans.

Results

Derivatives of fatty acids, carboxylic acid ester, and glycosides, were identified as the major bioactive compounds with potential anticancer properties in C. nutans leaf extract. Reductions in cell viability (0-78%) and proliferation (2-77%), as well as a synergistic anticancer effect, were identified in TNBC cells when treated with a combination of cisplatin and C. nutans. Furthermore, apoptotic induction via increased caspase-3/7 activity (MDA-MB-231: 2.73-fold; MDA-MB-468: 3.53-fold), and a reduction in cell invasion capacity to 36%, were detected in TNBC cells when compared to single cisplatin and C. nutans treatments. At the mRNA level, cisplatin and C. nutans differentially regulated specific genes that are responsible for proliferation and differentiation.

Conclusion

Our findings demonstrate that the combination of cisplatin and C. nutans represents a potential treatment for TNBC.

The antiproliferative and apoptotic potential of Clinacanthus nutans against human breast cancer cells through targeted apoptosis pathway

Clinacanthus nutans dichloromethane fraction (CN-Dcm) extract has previously been proven to suppress breast cancer (MCF7) cell proliferation. Despite this, the extrinsic and intrinsic apoptosis mechanisms involved in C. nutans extract-treated MCF7 cells are still unknown. This study was intended to subfractionate CN-Dcm extract using column chromatography and analyse the treated MCF7 cells using the CellTiter 96® AQueous One Solution Cell Proliferation (MTS) assay, Annexin V/propidium iodide (PI) assay, western blot, and reverse transcription-qualitative polymerase chain reaction (RT-qPCR). Out of nine subfraction extracts (SF1 to SF9), SF2 extract strongly inhibited MCF7 cells with the lowest IC50 value (23.51 ± 1.00 µg/mL) and substantially induced apoptosis in the MCF7 cells. In treated MCF7 cells, SF2 extract significantly upregulated the expression of P53, BAX, BID, caspase-8, caspase-9, and caspase-3, while downregulating the expression of BCL2. The presence of potential bioactive chemical compounds in the SF2 extract was identified using liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Thus, the SF2 extract has the potential to induce apoptosis in MCF7 cells through intrinsic and extrinsic pathways.

Anti-Inflammatory Effects of Phytochemical Components of Clinacanthus nutans

Recent studies on the ethnomedicinal use of Clinacanthus nutans suggest promising anti-inflammatory, anti-tumorigenic, and antiviral properties for this plant. Extraction of the leaves with polar and nonpolar solvents has yielded many C-glycosyl flavones, including schaftoside, isoorientin, orientin, isovitexin, and vitexin. Aside from studies with different extracts, there is increasing interest to understand the properties of these components, especially regarding their ability to exert anti-inflammatory effects on cells and tissues. A major focus for this review is to obtain information on the effects of C. nutans extracts and its phytochemical components on inflammatory signaling pathways in the peripheral and central nervous system. Particular emphasis is placed on their role to target the Toll-like receptor 4 (TLR4)-NF-kB pathway and pro-inflammatory cytokines, the antioxidant defense pathway involving nuclear factor erythroid-2-related factor 2 (NRF2) and heme oxygenase 1 (HO-1); and the phospholipase A₂ (PLA₂) pathway linking to cyclooxygenase-2 (COX-2) and production of eicosanoids. The ability to provide a better understanding of the molecular targets and mechanism of action of C. nutans extracts and their phytochemical components should encourage future studies to develop new therapeutic strategies for better use of this herb to combat inflammatory diseases.

The Efficient and Easy Micropropagation Protocol of Phyllanthus niruri

Phyllanthus niruri (P. niruri) or Dukung Anak is a herbal plant in the Phyllanthaceae family that has been used traditionally to treat various ailments such as diabetes, jaundice, flu and cough. P. niruri contains numerous medicinal benefits such as anti-tumor and anti-carcinogenic properties and a remedy for hepatitis B viral infection. Due to its beneficial properties, P. niruri is overharvested and wild plants become scarce. This study was conducted to develop an appropriate in vitro culture protocol for the mass production of P. niruri. An aseptic culture of P. niruri was established followed by multiplication of explants using different types of basal medium and its strength and plant growth regulators manipulation. This study also established the induction of in vitro rooting utilizing various types and concentrations of auxin. Treatment of Clorox^® with 30% concentration showed the lowest percentage (%) of contamination, 4.44% in P. niruri culture. Nodal segments of P. niruri were successfully induced in full-strength of Murashige and Skoog (MS) basal media with 2.33 number of shoots, 3.11 cm length of shoot and 27.91 number of leaves. In addition, explants in full-strength MS media without any additional cytokinin were recorded as the optimum results for all parameters including the number of shoots (5.0 shoots), the length of shoots (3.68 cm) and the number of leaves (27.33 leaves). Treatment of 2.5 µM indole-3-butyric acid (IBA) showed the highest number of roots (17.92 roots) and root length (1.29 cm). Rooted explants were transferred for acclimatization, and the plantlet showed over 80% of survival rate. In conclusion, plantlets of P. niruri were successfully induced and multiplied via in vitro culture, which could be a step closer to its commercialization.

Immunomodulatory potential of Clinacanthus nutans extracts in the co-culture of triple-negative breast cancer cells, MDA-MB-231, and THP-1 macrophages

Triple-negative breast cancer is the main type of breast carcinoma that causes mortality among women because of the limited treatment options and high recurrence. Chronic inflammation has been linked with the tumor microenvironment (TME) in breast cancer progression. Clinacanthus nutans (CN) has gained much attention because of its anticancer properties, but its mechanism remains unclear. We aimed to study the qualitative phytochemical content and elucidate the cytotoxicity effects of CN on human triple-negative breast cancer (TNBC), MDA-MB-231 and human macrophage-like cells such as THP-1 by using sulforhodamine B (SRB) assay. As highly metastatic cells, MDA-MB-231 cells can migrate to the distal position, the effect of CN on migration were also elucidated using the scratch assay. The CN effects on ameliorating chronic inflammation in TME were studied following the co-culture of MDA-MB-231/THP-1 macrophages. The cytokine expression levels of IL-6, IL-1β and tumor necrosis factor-alpha (TNF-α) were determined using ELISA assays. The results showed that both ethanolic and aqueous CN extracts contained alkaloid, phenol and tannin, flavonoid, terpenoid, glycoside and steroid. However, saponin was only found in the aqueous extract of CN. CN was not cytotoxic to both MDA-MB-231 and THP-1 cells. The ability of MDA-MB-231 to migrate was also not halted by CN treatment. However, CN ethanol extract decreased IL-6 at 25 μg/mL (p = 0.02) and 100 μg/mL (p = 0.03) but CN aqueous extract increased IL-6 expression at 50 μg/mL (p = 0.08) and 100 μg/mL (p = 0.02). IL-1β showed decreased expression after treated with CN ethanol and CN aqueous both at 25 μg/mL (p = 0.03). TNF-α were significantly decreased after CN ethanol treatment at concentration 25- (p = 0.001), 50- (p = 0.000) and 100 μg/mL (p = 0.000). CN aqueous extract slightly inhibited TNF-α at all 25–50- and 100 μg/mL (p = 0.001, p = 0.000, p = 0.000, respectively). Overall, CN acts by ameliorating the pro-inflammatory condition in the TME and may be a potential strategy for its anticancer mechanism on highly metastatic breast cancer condition. The major pathways that link both cancer and inflammation were NF-κB and STATs thus further study on the upstream and downstream pathways is needed to fully understand the mechanism of CN extracts in cooling the inflamed TME in breast cancer.

Shoot Multiplication and Callus Induction of Labisia pumila var. alata as Influenced by Different Plant Growth Regulators Treatments and Its Polyphenolic Activities Compared with the Wild Plant

This study aims to investigate whether the in vitro-cultured L. pumila var. alata has higher antioxidant activity than its wild plant. An 8-week-old L. pumila var. alata nodal segment and leaf explants were cultured onto Murashige and Skoog (MS) medium supplemented with various cytokinins (zeatin, kinetin, and 6-benzylaminopurine (BAP)) for shoot multiplication and auxins (2,4-dichlorophenoxyacetic acid (2,4-D) and picloram) for callus induction, respectively. The results showed that 2 mg/L zeatin produced the optimal results for shoot and leaf development, and 0.5 mg/L 2,4-D produced the highest callus induction results (60%). After this, 0.5 mg/L 2,4-D was combined with 0.25 mg/L cytokinins and supplemented to the MS medium. The optimal results for callus induction (100%) with yellowish to greenish and compact texture were obtained using 0.5 mg/L 2,4-D combined with 0.25 mg/L zeatin. Leaves obtained from in vitro plantlets and wild plants as well as callus were extracted and analyzed for their antioxidant activities (DPPH and FRAP methods) and polyphenolic properties (total flavonoid and total phenolic content). When compared with leaf extracts of in vitro plantlets and wild plants of L. pumila var. alata, the callus extract displayed significantly higher antioxidant activities and total phenolic and flavonoid content. Hence, callus culture potentially can be adapted for antioxidant and polyphenolic production to satisfy pharmaceutical and nutraceutical needs while conserving wild L. pumila var. alata.