Anti-Obesity Effects of the Larval Powder of Steamed and Lyophilized Mature Silkworms in a Newly Designed Adult Mouse Model

Recently, mature silkworms (MS) of Bombix mori have been considered a potential nutraceutical, with a number of health benefits reported for steamed and lyophilized MS powder (SMSP). However, no obesity-related effects have been reported for SMSP. In the present study, anti-obesity effects of SMSP were investigated in adult mice in vivo, aged 12 weeks at the onset of SMSP treatment, fed a normal diet (ND) and a high-fat diet (HFD), respectively, for 12 weeks. SMSP significantly suppressed body weight gain, intra-abdominal adipose tissue, and food efficiency in both ND-fed and HFD-fed adult mice. In addition, SMSP significantly decreased food intake and liver weight in HFD-fed mice, indicating that SMSP suppressed appetite and simultaneously reduced the conversion of feed into body weight in HFD-fed mice. SMSP also significantly lowered the serum levels of glucose, triglyceride, total cholesterol, low-density lipoprotein cholesterol, asparagine transaminase, alanine transaminase, and alkaline phosphatase. However, SMSP had no significant effect on the weights of the kidney, spleen, or thymus or the serum levels of blood urea nitrogen and creatinine. Taken together, the above results suggest that SMSP has potent anti-obesity effects and is safe for long-term use as a potential therapeutic and/or nutraceutical in both obese patients and non-obese individuals.

Automated summary

The present study investigated the anti-obesity effects of mature silkworm powder in adult mice. The results showed that mature silkworm powder significantly suppressed body weight gain, intra-abdominal adipose tissue, and food efficiency in both normal diet-fed and high-fat diet-fed mice. It also decreased food intake and liver weight in high-fat diet-fed mice, indicating appetite suppression and reduced conversion of feed into body weight. Furthermore, mature silkworm powder lowered the levels of glucose, triglyceride, cholesterol, liver enzymes, and alkaline phosphatase in the serum. These findings suggest that mature silkworm powder has potent anti-obesity effects and is safe for long-term use as a potential therapeutic and/or nutraceutical.