Intragastric administration of cinnamaldehyde induces changes in body temperature via TRPA1.

The transient receptor potential (TRP) channel family, including TRPA1, is known to be involved in temperature sensing and response. Previous studies have shown that intragastric administration of cinnamaldehyde (a typical TRPA1 agonist) can change body temperature, but the role of TRPA1 in this response is not clear. In this study, we found that intragastric administration of cinnamaldehyde increased in the intrascapular brown adipose tissue (IBAT) and rectal temperatures.

Allyl isothiocyanate increases carbohydrate oxidation through enhancing insulin secretion by TRPV1.

The transient receptor potential (TRP) V1 is a cation channel belonging to the TRP channel family and it has been reported to be involved in energy metabolism, especially glucose metabolism. While, we have previously shown that intragastric administration of allyl isothiocyanate (AITC) enhanced glucose metabolism via TRPV1, the underlying mechanism has not been elucidated. In this study, we examined the relationship between insulin secretion and the increase in carbohydrate oxidation due to AITC.

Vagus nerve is involved in the changes in body temperature induced by intragastric administration of 1,8-cineole via TRPM8 in mice.

Transient Receptor Potential Melastatin 8 (TRPM8) is a cold receptor activated by mild cold temperature (<28°C). TRPM8 expressed in cutaneous sensory nerves is involved in cold sensation and thermoregulation. TRPM8 mRNA is detected in various tissues, including the gastrointestinal mucosa, and in the vagal afferent nerve.

β-Nicotinamide Mononucleotide, an Anti-Aging Candidate Compound, Is Retained in the Body for Longer than Nicotinamide in Rats.

The turnover of the oxidized form of nicotinamide adenine dinucleotide (NAD) has attracted interest in regard to longevity. Thus, compounds that can rapidly increase the cellular NAD concentration have been surveyed by many researchers. Of those, β-nicotinamide mononucleotide (β-NMN) has been focused on.

Inhibition of Large Neutral Amino Acid Transporters Suppresses Kynurenic Acid Production Via Inhibition of Kynurenine Uptake in Rodent Brain.

The tryptophan metabolite, kynurenic acid (KYNA), is a preferential antagonist of the α7 nicotinic acetylcholine receptor and N-methyl-D-aspartic acid receptor at endogenous brain concentrations. Recent studies have suggested that increases of brain KYNA levels are involved in psychiatric disorders such as schizophrenia and depression, and regulation of KYNA production has become a new target for treatment of these diseases. Kynurenine (KYN), the immediate precursor of KYNA, is transported into astrocytes via large neutral amino acid transporters (LATs).

Thermal conditions influence changes in body temperature induced by intragastric administration of capsaicin in mice.

Capsaicin has been reported to have unique thermoregulatory actions. However, changes in core temperature after the administration of capsaicin are a controversial point. Therefore, we investigated the effects of environmental thermal conditions on changes in body temperature caused by capsaicin in mice.

Enhancement of Fat Oxidation by Licorice Flavonoid Oil in Healthy Humans during Light Exercise.

Licorice flavonoid oil (LFO) is a new functional food ingredient consisting of hydrophobic licorice polyphenols in medium-chain triglycerides. Recent studies reported that LFO prevented and ameliorated diet-induced obesity via the regulation of lipid metabolism-related gene expression in the livers of mice and rats, while it reduced body weight in overweight human subjects by reducing total body fat. However, the direct effects of LFO on energy metabolism have not been studied in human subjects.

Intragastric administration of allyl isothiocyanate reduces hyperglycemia in intraperitoneal glucose tolerance test (IPGTT) by enhancing blood glucose consumption in mice.

We investigated the effects of allyl isothiocyanate (AITC) on the blood glucose levels of mice using an intraperitoneal glucose tolerance test. The intragastric administration of 25 mg/kg body weight AITC reduced the increase in blood glucose level after 2 g/kg body weight glucose was given intraperitoneally, compared with that of control mice. To elucidate the mechanism responsible for the reduction, respiratory gas analysis employing (13)C-labeled glucose was performed.

Intragastric administration of allyl isothiocyanate increases carbohydrate oxidation via TRPV1 but not TRPA1 in mice.

The transient receptor potential (TRP) channel family is composed of a wide variety of cation-permeable channels activated polymodally by various stimuli and is implicated in a variety of cellular functions. Recent investigations have revealed that activation of TRP channels is involved not only in nociception and thermosensation but also in thermoregulation and energy metabolism. We investigated the effect of intragastric administration of TRP channel agonists on changes in energy substrate utilization of mice.