This study was designed to clarify the relationship between Sho, which represents a clinical status in oriental medicine, and the clinical parameter in type 2 diabetes mellitus (DM). In 65 patients [male 27 (mean age: 60.9±12.0) and female 38 (64.9±8.4)] with type 2 DM, we determined the incidence of Sho [In/Yo (yin/yang) and Kyo/Jitsu (xu/shi)], measured the indices of insulin resistance (fasting plasma insulin level: F-IRI and HOMA-IR), and analyzed the relationship between them. The incidences of In, intermediate, Yo were 30.8%, 32.3% and 36.9%, respectively, while the incidence of Kyo, intermediate, Jitsu were 30.8%, 33.8%, and 35.4%, respectively. The incidences of combined Sho represented as Yo-Jitsu, intermediate-intermediate, In-Kyo, Yo-Kyo, intermediate-Jitsu, Yo-intermediate, In-intermediate and intermediate-Kyo were 26.2%, 21.5%, 18.5%, 10.8%, 7.7%, 6.2%, 6.2% and 3.1%, respectively. F-IRI was significantly higher in patients with Jitsu than those with Kyo (p=0.044) and significantly higher in patients with Yo-Jitsu than those with In-Kyo (p=0.033). HOMA-IR is significantly higher in patients with Yo-Jitsu than those with In-Kyo (p=0.017). Our study indicated that the incidences of In and Yo were almost the same and those of Kyo and Jitsu were also nearly the same in patients with type 2 DM. In addition, our study suggested that Sho of Jitsu and Yo-Jitsu could be related with the degree of insulin resistance in patients with type 2 DM.

The recent development of molecular biology enables us to identify three abnormal insulins (insulin Chicago, insulin LosAngeles and insulin Wakayama). In Japan, three pedigrees in which affected individuals secrete [Leu^A3] insulin (insulin Wakayama) have been identified. In each family, hyperinsulinemia associated with an abnormally elevated insulin to C-peptide molar ratio was demonstrated to occur in an autosomal dominant pattern of inheritance. In accordance with in vivo observations, semisynthetic [Leu^A3] insulin demonstrated reduced in vitro receptor binding and biological activity relative to the human standard. The development of diabetes mellitus in affected family members was not uniform, was influenced by aging, and was different among families. Patients with impaired glucose tolerance demonstrated reduced insulin secretory reserve. Some of these features are thought to resemble the nature of noninsulin dependent diabetes mellitus (NIDDM).
Therefore, insulin Wakayama may be an useful model for the study of the development of NIDDM.