Pyridine Alkaloids

Nicotinamide is a form of vitamin B3 or niacin. Nicotinamide Hydrochloride inhibits SIRT2 activity (IC₅₀: 2 μM). Nicotinamide also inhibits SIRT1. Nicotinamide increases cellular NAD₊, ATP, ROS levels. Nicotinamide inhibits tumor growth and improves survival. Nicotinamide also has anti-HBV activity.

Nicotinamide riboside Chloride, an orally active NAD⁺ precursor, increases NAD⁺ levels and activates SIRT1 and SIRT3. Nicotinamide riboside Chloride is a source of vitamin B3 (niacin) and enhances oxidative metabolism, protection against high fat diet-induced metabolic abnormalities. Nicotinamide riboside Chloride reduces cognitive deterioration in a transgenic mouse model of Alzheimer’s disease.

Cyclopamine is a Hedgehog (Hh) pathway antagonist with an IC₅₀ of 46 nM in the Hh cell assay. Cyclopamine is also a selective Smo inhibitor.

Quinolinic acid, an endogenous metabolite of tryptophan, is a N-methyl-D-aspartate receptor (NMDA receptor) agonist. Quinolinic acid increases glutamate efflux, induces the generation of ROS, activates nitric oxide synthase, produces excessive NO, leading to calcium ion influx and neuronal apoptosis.

Piperlongumine is a alkaloid, possesses ant-inflammatory, antibacterial, antiangiogenic, antioxidant, antitumor, and antidiabetic activities. Piperlongumine induces ROS, and induces apoptosis in cancer cell lines. Piperlongumine shows anti-cardiac fibrosis activity, suppresses myofibroblast transformation via suppression of the ERK1/2 signaling pathway. Piperlongumin could be used in the study of migrasome.

Kuanoniamine A is a pyridoacridine alkaloid and also an anticancer agent. Kuanoniamine A inhibits DNA synthesis, induces apoptosis, and regulates the cell cycle by reducing the proportion of cells in the G2/M phase. Kuanoniamine A inhibits the proliferation of human lymphocytes. Kuanoniamine A can be used in research related to breast cancer, glioma, non-small cell lung cancer, and melanoma.

Clavolonine is a lycopodane-group Lycopodium alkaloid.Clavolonine can be found in the aerial parts of Huperzia saururus.

Hupehenisine (Dihydrojervine) is a semisynthetic Veratrum alkaloid. Hupehenisine inhibits prostate cancer cell proliferation. Hupehenisine can be used for the research of prostate cancer.

Sanguinarine (Sanguinarin) chloride, a benzophenanthridine alkaloid derived from the root of Sanguinaria Canadensis, can stimulate apoptosis via activating the production of reactive oxygen species (ROS). Sanguinarine-induced apoptosis is associated with the activation of JNK and NF-κB.

Trigonelline is an alkaloid with potential antidiabetic activity that can be isolated from Trigonella foenum-graecum L or Leonurus artemisia. Trigonelline is a potent Nrf2 inhibitor that blocks Nrf2-dependent proteasome activity, thereby enhancing apoptosis in pancreatic cancer cells. Trigonelline also has anti-HSV-1, antibacterial, and antifungal activity and induces ferroptosis.

Metyrapone (Su-4885) is a potent and orally active 11β-hydroxylase inhibitor and an autophagy activator, also inhibits the production of aldosterone. Metyrapone inhibits synthesis of endogenous adrenal corticosteroid, decreases glucocorticoid levels, and also affects behavior and emotion. In addition, Metyrapone increases the efficiency of autophagic process via downregulation of mTOR pathway, and interacts with Pseudomonas putida cytochrome P-450. Metyrapone can be used for researching Cushing's syndrome and depression.

NNK is a nicotine-nitrosated derivative. NNK simultaneously stimulates Bcl2 phosphorylation exclusively at Ser⁷⁰ and c-Myc at Thr⁵⁸ and Ser⁶² through activation of both ERK1/2 and PKCα. NNK induces survival and proliferation of human lung cancer cells. NNK can be used for lung cancer mice model structure.

Pyridoxine hydrochloride (Pyridoxol; Vitamin B6) is a pyridine derivative. Pyridoxine (Pyridoxol; Vitamin B6) exerts antioxidant effects in cell model of Alzheimer's disease via the Nrf-2/HO-1 pathway.

Atazanavir (BMS-232632) is a highly selective and orally active HIV-1 protease inhibitor . Atazanavir is a substrate and inhibitor of CYP3A4, and an inhibitor of P-glycoprotein (P-gp). Atazanavir is also a SARS-CoV 3CL^pro inhibitor with an IC₅₀ of 3.49 μM. Atazanavir inhibits cardiac fibrosis, hyperlipidemia and induces malignant glioma death.

N-Methylnicotinamide is an endogenous metabolite with antithrombotic effect. N-Methylnicotinamide via production/release of prostacyclin inhibits arterial thrombosis development. N-Methylnicotinamide is also the N-methylation product from nicotinamide catalyzed by N-methyltransferase within nicotinate and nicotinamide metabolism pathway.

Tomatidine acts as an anti-inflammatory agent by blocking NF-κB and JNK signaling. Tomatidine activates autophagy either in mammal cells or C elegans.

Norharmane (Norharman), a β-carboline alkaloid, is a potent and reversible monoamine oxidase inhibitor, with IC₅₀ values of 6.5 and 4.7 μM for MAO-A and MAO-B, respectively. Norharmane causes antidepressant responses. Norharmane is also a prospective anti-cancer photosensitizer. Norharmane alters polar auxin transport (PAT) by inhibiting PIN2, PIN3 and PIN7 transport proteins, thus causing a significant inhibitory effect on the growth of Arabidopsis thaliana seedlings.

Nicotinic acid riboside is a NAD⁺ precursor in human cells. Nicotinic acid riboside is an authentic intermediate of human NAD⁺ metabolism.

Cotinine ((-)-Cotinine) is an orally active alkaloid found in tobacco and is the primary metabolite of nicotine. Cotinine is metabolized by CYP2A13 into trans-3'-hydroxycotinine. Cotinine is used as a biomarker to measure exposure to tobacco smoke components. Cotinine has vasodepressor activity. The mixture of cotinine and nicotine (Nicotine) has antiproliferative activity against pterygium. (S)-(-)-Cotinine activates nicotinic acetylcholine receptors (nAChR) in a calcium-dependent manner, leading to the release of dopamine (Dopamine, HY-B0451). Cotinine ((-)-Cotinine) is used in research related to cardiovascular and inflammatory diseases.

(-)-Securinine is plant-derived alkaloid and also a GABA_A receptor antagonist.