Type-1 diabetes mellitus (T1DM) is associated with metabolic changes leading to alterations in glucose and lipid handling. While T1DM-associated effects on many major plasma lipids have been characterised, such effects on plasma free fatty acids (FFA) have not been fully examined. Using gas chromatography–mass spectrometry, we measured the plasma concentrations of FFA species in individuals with T1DM (n = 44) and age/sex-matched healthy controls (n = 44). Relationships between FFA species and various parameters were evaluated. Plasma concentrations of myristate (14:0), palmitoleate (16:1), palmitate (16:0), linoleate (18:2), oleate (18:1c9), cis-vaccenate (18:1c11), eicosapentaenoate (20:5), arachidonate (20:4) and docosahexanoate (22:6) were reduced in the T1DM group (p < 0.0001 for all, except p = 0.0020 for eicosapentaenoate and p = 0.0068 for arachidonate); α-linolenate (18:3) and dihomo-γ-linolenate (20:3) concentrations were unchanged. The saturated/unsaturated FFA ratio, n-3/n-6 ratio, de novo lipogenesis index (palmitate (main lipogenesis product)/linoleate (only found in diet)) and elongase index (oleate/palmitoleate) were increased in the T1DM group (p = 0.0166, p = 0.0089, p < 0.0001 and p = 0.0008 respectively). The stearoyl-CoA desaturase 1 (SCD1) index 1 (palmitoleate/palmitate) and index 2 (oleate/stearate) were reduced in T1DM (p < 0.0001 for both). The delta-(5)-desaturase (D5D) index (arachidonate/dihomo-γ-linolenate) was unchanged. Age and sex had no effect on plasma FFA concentrations in T1DM, while SCD1 index 1 was positively correlated (p = 0.098) and elongase index negatively correlated with age (p = 0.0363). HbA1c was negatively correlated with all plasma FFA concentrations measured except α-linolenate and dihomo-γ-linolenate. Correlations were observed between plasma FFA concentrations and cholesterol and HDL concentrations, but not LDL concentration or diabetes duration. Collectively, these results aid our understanding of T1DM and its effects on lipid metabolism.

1 型糖尿病 (T1DM) 与导致葡萄糖和脂质处理改变的代谢变化有关。虽然已经表征了 T1DM 对许多主要血浆脂质的影响，但这种对血浆游离脂肪酸 (FFA) 的影响尚未得到充分检验。使用气相色谱-质谱法，我们测量了 T1DM ( n  = 44) 和年龄/性别匹配的健康对照 (n = 44) 个体中 FFA 种类的血浆浓度。评估了 FFA 种类与各种参数之间的关系。肉豆蔻酸 (14:0)、棕榈油酸 (16:1)、棕榈酸 (16:0)、亚油酸 (18:2)、油酸 (18:1c9)、顺-十六酸 (18:1c11)、二十碳五烯酸 (20) 的血浆浓度:5)、花生四烯酸 (20:4) 和二十二碳六烯酸 (22:6) 在 T1DM 组中减少（p < 0.0001，除二十碳五烯酸p  = 0.0020 和花生四烯酸p  = 0.0068 外）；α-亚麻酸 (18:3) 和二高-γ-亚麻酸 (20:3) 浓度没有变化。T1DM 组的饱和/不饱和 FFA 比率、n-3/n-6 比率、从头脂肪生成指数（棕榈酸盐（主要脂肪生成产物）/亚油酸盐（仅在饮食中发现））和延长酶指数（油酸盐/棕榈油酸盐）增加( p  = 0.0166, p  = 0.0089, p  < 0.0001 和p = 0.0008）。T1DM 中的硬脂酰辅酶 A 去饱和酶 1 (SCD1) 指数 1（棕榈油酸酯/棕榈酸酯）和指数 2（油酸酯/硬脂酸酯）降低（两者的 p < 0.0001）。δ-(5)-去饱和酶 (D5D) 指数（花生四烯酸/二高-γ-亚麻酸）没有变化。年龄和性别对 T1DM 患者血浆 FFA 浓度没有影响，而 SCD1 指数 1 与年龄呈正相关（p  = 0.098），延伸酶指数与年龄呈负相关（p = 0.0363)。HbA1c 与除 α-亚麻酸盐和二高-γ-亚麻酸盐外的所有血浆 FFA 浓度呈负相关。在血浆 FFA 浓度与胆固醇和 HDL 浓度之间观察到相关性，但与 LDL 浓度或糖尿病病程无关。总的来说，这些结果有助于我们了解 T1DM 及其对脂质代谢的影响。