Alleviation of Metabolic Disturbance by Substituting Kanjang High in Bacillus for Salt through Modulation of Gut Microbiota in Estrogen-Deficient Rats

Abstract

A high salt intake may exacerbate menopausal symptoms and substituting for different types of traditionally made kanjang (TMK; soy sauce) may prevent it. This study examined whether substituting salt with lyophilized TMK containing low and high Bacillus and biogenic amines in a high-fat diet might modulate the menopausal symptoms and the energy, glucose, and lipid metabolism in ovariectomized (OVX) rats. They were categorized into salt (Control), TMK with high Bacillus and low biogenic amines (HBLB), TMK with high Bacillus and high biogenic amines (HBHB), TMK with low Bacillus and low biogenic amines (LBLB), and TMK with low Bacillus and high biogenic amines (LBHB). Sham-operated rats consumed the same diet as the Control. HBLB, HBHB, and LBHB prevented increased tail skin temperature compared to the Control. HBHB and HBLB partially inhibited the increased weight gain and abdominal fat mass by reducing the food efficiency without changing the serum 17β-estradiol concentrations. Serum glucose and insulin concentrations and the insulin resistance index by the homeostatic model assessment for insulin resistance showed a positive association for weight gain. HBLB and HBHB decreased the serum malondialdehyde and tumor-necrosis factor-α levels. Hepatic triglyceride storage was lower in all TMK groups than in the Control, while hepatic glycogen accumulation was higher in the HBLB, HBHB, and LBHB groups than in the Control and LBLB groups. Accordingly, the mRNA expression of peroxisome proliferator-activated receptors-γ(PPAR-γ) was higher in the HBLB and HBHB groups compared to the Control, and that of fatty acid synthase was opposite to PPAR-γ expression. However, HBLB and HBHB improved dyslipidemia and insulin resistance compared to the Control, but their improvement did not reach that of the Normal-control. The acetic acid concentrations in the portal vein were lower in the LBLB than in the Control, while the butyric acid contents were higher in the LBHB and HBLB groups than in the Control. HBHB, HBLB, and LBHB elevated Akkermansia and Lactobacillus, and HBLB and LBLB increased Bacteroides and Ruminococcus compared to the Control. Polycyclic aromatic hydrocarbon degradation, bile acid synthesis, and unsaturated fatty acid biosynthesis were significantly higher in the HBLB group than in the Control group. In conclusion, substituting salts to TMK with a high Bacillus content regardless of the bioamine contents partially improved the menopausal symptoms and metabolic disturbance in estrogen-deficient animals.

Inverse association of daily fermented soybean paste (“Jang”) intake with metabolic syndrome risk, especially body fat and hypertension, in men of a large hospital-based cohort

“…Miso intake, the Japanese soybean paste containing salt, has been reported to attenuate sympathovagal imbalance toward a more parasympathetic nerve dominant state and brain sodium sensitivity in mice administered a high-sodium solution injection (0.28 M sodium) and salt-sensitive rats given 1.3% salt solution (52,53). Chungkookjang, Doenjang, Kanjang, and Kochujang intakes have been shown to alleviate hyperglycemia, dyslipidemia, obesity, and hypertension in earlier human and animal studies (6,(13)(14)(15)(16)(17). The Bacillus species in Chungkookjang, Doenjang, Kanjang, and Kochujang have been extensively studied, and certain isolated Bacillus species have probiotic characteristics.…”

“…Previous human and animal studies have shown that consuming Chungkookjang, Doenjang, Kanjang, and Kochujang lowers weight gain and improves insulin resistance, dyslipidemia, and hyperglycemia (6,(13)(14)(15)(16)(17). Jang is used as a substitute for table salt and could be one of the potential candidates to reduce MetS risk.…”

Inverse association of a traditional Korean diet composed of a multigrain rice-containing meal with fruits and nuts with metabolic syndrome risk: The KoGES

“…Hansik is known to be high in salt, and there have been diverse opinions about the health benefits of salt intake ( 23 ). However, the salts in hansik mainly come from jangs made with solar salts and fermented soybeans, which have been reported to be beneficial for metabolic diseases ( 24 – 26 ). The present study demonstrated that a high meal containing multigrain, fruits, and nuts and a low intake of fried foods based on a K diet -index composed of 14 hansik-related components was inversely associated with MetS risk.…”

Improvement of Estrogen Deficiency Symptoms by the Intake of Long-Term Fermented Soybeans (Doenjang) Rich in Bacillus Species through Modulating Gut Microbiota in Estrogen-Deficient Rats

“…The rats were anesthetized with subcutaneous injections of a ketamine/xylazine mixture (100 and 10 mg/kg body weight) during the ovariectomy (OVX) procedure [ 11 ]. After a mid-ventral incision, each ovary was removed by ligating the most proximal part of each oviduct, and both ovaries were dissected with scissors.…”

“…The intake of traditionally made kanjang with high Bacillus species (spp.) but not biogenic amine contents affects the gut microbiota composition to improve energy, fatty acid biosynthesis, and bile acid metabolism in estrogen-deficient rats [ 11 ]. Therefore, the bacteria and biogenic amines contained in TMD could also affect estrogen deficiency symptoms by altering the isoflavonoid content and gut microbiota composition.…”