Vildagliptin, a dipeptidyl peptidase-4 inhibitor, reduces betel-nut induced carcinogenesis in female mice

The antidiabetic drug pioglitazone ameliorates betel-nut-induced carcinogenesis in mice by restoring normal lipid metabolism, reducing oxidative stress, and inducing apoptosis

CONTEXT

Oral administration (2 mg mL-1) of aqueous extract of betel nut (AEBN) for 24 weeks induced oncogenic alterations in the liver of female Swiss Albino mice concomitant with aberrant lipid metabolism, overactivation of Akt/mTOR signaling, and loss of apoptosis.

AIM

This study was designed to investigate the potential of repurposing the antidiabetic drug pioglitazone for alleviating AEBN-induced carcinogenesis.

METHODS

Sera of animals were evaluated for lipid profile and free fatty acid levels. Liver tissues were investigated for oxidative stress, histopathology, and expression of proteins involved in lipid metabolism and oncogenesis by western blotting. Apoptosis was determined using TUNEL assay.

RESULTS

Coadministration of pioglitazone (10 mg kg-1 b.w) with AEBN for 8 weeks restored normal lipid profile and AMPK/ACC signaling, reduced FASN and HMGCR expressions and oxidative stress, and actively induced Akt/mTOR-mediated apoptosis in the liver.

CONCLUSIONS

Pioglitazone can effectively alleviate AEBN-induced carcinogenesis in mice.

Anagliptin promotes apoptosis in mouse colon carcinoma cells via MCT-4/lactate-mediated intracellular acidosis

Cancer cells frequently exhibit an acidic extracellular microenvironment, where inversion of the transmembrane pH gradient is associated with tumor proliferation and metastasis. To elucidate a new therapeutic target against cancer, the current study aimed to determine the mechanism by which the dipeptidyl peptidase-4 inhibitor anagliptin regulates the cellular pH gradient and concomitant extracellular acidosis during cancer progression. A total of 5x10⁵ CT-26 cells (resuspended in phosphate buffer saline) were injected subcutaneously in the right flank of male BALB/c mice (weighing 25-28 g). The tumor samples were harvested, and lactate was detected using a lactate assay kit. Immunohistochemistry was used to detect the Ki67 and PCNA. MTT assay and flow cytometric were used to detect cell viability. Intracellular pH was detected by fluorescence pH indicator. The results revealed that anagliptin effectively reduced tumor growth, but did not affect the body weight of treated mice. Anagliptin reduced the accumulation of lactate in tumor sample. Treatment with anagliptin stimulated the apoptosis of CT-26 cells. And lactate excretion inhibition is accompanied by an increase in extracellular pH (pHe) after treatment with anagliptin. Furthermore, anagliptin induced intracellular acidification and reversed the low pHe gradient via monocarboxylate transporter-4 (MCT-4)-mediated lactate excretion. Additionally, anagliptin reversed the aberrant transmembrane extracellular/intracellular pH gradient by suppressing MCT-4-mediated lactate excretion, while also reducing mitochondrial membrane potential and inducing apoptosis. These data revealed a novel function of anagliptin in regulating lactate excretion from cancer cells, suggesting that anagliptin may be used as a potential treatment for cancer.

Investigation into the role of anti-diabetic agents in cachexia associated with metastatic cancer

Cancer cachexia (CC) is a syndrome associated with cancer, and the global burden is increasing rapidly. Alteration in carbohydrate, lipid and protein metabolism along with systemic inflammation are characteristics of CC. Until now the available treatment for CC is limited to controlling inflammation and nutrition. Anti-diabetics are widely used agents to treat diabetics, this agent's act by regulating the carbohydrate metabolism, also they are known to have beneficial effects in maintaining protein and lipid balance. Role of anti-diabetics in cancer is being evaluated continuously and biguanides, dipeptidyl peptidase 4 (DPP4) inhibitors and Sodium glucose co-transporter 2 (SGLT2) inhibitors have proven anti-cancer potential. In this study, metastatic B16-F1 cell line induced cancer cachexia model used to evaluate potential of biguanides (metformin), DPP-4 inhibitors (teneligliptin and vildagliptin) and SGLT2 inhibitors (empagliflozin and dapagliflozin) in cancer cachexia. Our results suggest that anti-diabetic agents have potential to decrease rate of proliferation of tumor, restrict body mass markers, decrease inflammation, regulate carbohydrate mechanism and induce skeletal muscle hypertrophy. These findings may be helpful in management of cancer cachexia and increase the quality of life and survival chances of cancer cachexia patient.