The ShengMai formula (SMF), which was first recorded in Yi Xue Yuan Li, consists of
P. ginseng root (Renshen),
Ophiopogon japonicus root (Maidong), and
Schisandra chinensis fruit (Wuweizi) with a dosage proportion of 5:3:1.5. It is normally prepared as ShengMai powder (SMP; or ShengMai san, SMS), ShengMai yin (SMY), ShengMai injection (SMI), etc., for clinical use. SMF is a classic tonic prescription for the treatment of tuberculosis, chronic bronchitis, cough due to neurasthenia, and heart failure
[127]. SMI, an intravenous dosage form of SMF, is used to treat acute myocardial infarction, cardiogenic shock, toxic shock, hemorrhagic shock, coronary heart disease, endocrine disorders, and other diseases due to a deficiency of qi and yin, with low toxicity
[128][129]. SMI is highly recommended for use in combination with antibiotics for community-acquired pneumonia in clinical guidelines
[2]. A meta-analysis including 17 randomized controlled trials (RCTs) and 860 patients with septic shock suggested that adding SMI to conventional Western medicine treatment further reduced the number of ineffective shock treatments (
p < 0.0001) and reduced the blood lactate concentration at 12 h (
p < 0.001), 24 h (
p < 0.0001), and 72 h (
p = 0.002)
[130].
SMI protects multiple organs by regulating immunity, inflammation, apoptosis, and energy metabolism. SMI also protected the intestinal mucosal barrier of mice mainly through regulating the NF-κB–pro-inflammatory factor–myosin light-chain kinase (MLCK)–TJ cascade. Decreasing trends for inflammatory factors including interferon-γ (IFN-γ), TNF-α, and IL-2 were observed in the sera of mice receiving SMI at 1.5 mL/kg. The content of occludin increased and MLCK protein decreased in SMI-treated mice compared with the endotoxemia mouse model group (
p < 0.05 or
p < 0.01)
[131]. SMI could induce myocardial mitochondrial autophagy via the caspase-3/Beclin-1 axis to protect myocardial mitochondria in septic mice
[132]. A study by Chai et al. on CLP rats suggested that the regulation of taurine and taurine metabolism, as well as arginine and proline metabolism, etc., could be the key mechanism in the treatment of sepsis
[133].
Zheng et al. recently reviewed, in Chinese, the material composition, preclinical pharmacokinetic, and pharmacodynamic studies of SMI
[134]. Several research groups have analyzed the chemical compositions of SMF preparations and identified the main constituents as ginsenosides (originating from
P. ginseng), steroidal saponins (from
O. japonicus), lignans (from
S. chinensis), and flavonoids (mainly from
O. japonicus). Using LC-IT-TOF/MS and a diagnostic fragment-ion-based extension strategy, Zheng et al. detected and identified more than 30 ginsenosides and 20 lignans from SMI
[135]. Zhao et al. identified or partially characterized 87 herbal compounds in SMI and selected 6 bioactive constituents (four ginsenosides (i.e., Rg
1, Re, Rb
1, and Rd) and 2 lignans (i.e., schisandrol A and schisandrol B) with high content levels as quality markers (Q-markers). The total content range for these selected Q-markers in 10 batches of SMI was 13.8–22.5 mg/mL
[136]. Wu et al. identified 92 compounds (i.e., 49 ginsenosides, 31 lignans, 5 steroidal saponins, and 7 homoisoflavanones) in SMP and discovered a class of 25-hydroxyginsenosides for the first time
[137]. In a study by Cheng et al., 10 compounds (the ginsenosides Rb
1, Rb
2, Rc, Rd, Re, Rg
1, and Rh
1; compound K; ophiopogonin D; and schisandrol A) were measured in SMP, and the contents of these herbal constituents were found to vary by up to several hundredfolds among five pharmaceutical manufacturers
[138]. In their study, Zheng et al. selected eight compounds (the ginsenosides Rf, Rb
1, Rg
2, and Rb
2; schisandrol A; schisandrol B; methylophiopogonanone A; and schisandrin B) as Q-markers to evaluate the batch-to-batch consistency of SMF; ginsenoside Rb
1, ranging from 2046.1 μg/g (1.84 μmol/g) to 5975.8 μg/g (5.39 μmol/g), was found to be the dominant component in SMF, followed by ginsenoside Rg
2 (838.3–2091.64 μg/g; 1.07–2.66 μmol/g) and ginsenoside Rb
2 (567.2–1989.9 μg/g; 0.53–1.84 μmol/g). The batch-to-batch chemical variation among 10 batches of SMF ranged from 27.9% (for ginsenoside Rf) to 113.95% (for schisandrol B)
[139]. Li et al. established a seven-marker-based quality standard to quantify seven ginsenosides (i.e., the ginsenosides Rf, Rd, Rc, Re, Rb
1, Rb
2, and Rg
1) in SMI, which was then used to evaluate the quality consistency of 22 batches of SMI
[140]. Li et al. detected 62 compounds in SMI and established a quantitative assay for the determination of 21 main components, including 14 saponins, 6 lignans, and 1 pyranoglucoside, and found the contents of these 21 components to vary widely amongst 10 batches
[141].
Lu et al. established a TCM–components–core targets–key pathway network platform to investigate the mechanism of SMI’s effects in sepsis. SMI was found to mainly affect several signaling pathways, suggesting that SMI could regulate immunity, inflammation, apoptosis, and energy metabolism for the protection of multiple organs. Gene ontology (GO) enrichment analysis further indicated that the bioactive SMI constituents altered the pathophysiology of sepsis through the regulation of various biological processes
[142]. SMP protected against I/R-induced blood–brain barrier (BBB) dysfunction by significantly upregulating ZO-1 and claudin-5 under oxygen-glucose deprivation/reoxygenation (OGD/R), as well as reducing matrix metalloproteinase 2/9 (MMP-2/9) levels and the phosphorylation of myosin light-chain (MLC) through the ROCK/cofilin signaling pathway
[143].
Zhan et al. developed and validated a sensitive LC-MS/MS method for the simultaneous quantification of 11 SMI compounds in rat serum and applied it to a pharmacokinetic study in rats after a single intravenous administration of SMI. The 11 constituents were ppt-type ginsenosides (i.e., the ginsenosides Rg
1, Re, Rf, and Rg
2), ppd-type ginsenosides (i.e., the ginsenosides Rb
1, Rd, and Rc), ophiopogonin (ophiopogonin D), and lignans (i.e., schisandrol A, schisandrol B, and schisandrin B)
[144][145]. A total of 30 compounds (23 prototype components and 7 metabolites) were detected and characterized in the plasma of rats after they received SMS (8 g/kg)
[146][147]. Further, ppt-type ginsenosides were eliminated rapidly through urinary, biliary, and fecal excretions (plasma
t1/2â, 0.60–0.82 h; MRT, 0.22–0.46 h), whereas the ppd-type ginsenosides Rb
1, Rd, and Rc exhibited slow elimination through biliary and urinary excretions (MRT, 23.0‒28.6 h). Ophiopogonin D was mainly excreted in bile in the metabolized forms. Schisandrol A, schisandrol B, and schisandrin B, with low contents in SMI, were found to be eliminated quickly (plasma
t1/2â, 0.51‒1.98 h; MRT, 0.51‒2.50 h) and accumulated in these tissues. Lignans were mainly excreted in their metabolized form, as indicated by the very low biliary, urinary, and fecal excretion of the unchanged forms
[144][145]. SMI, within the concentration range of 30% (volume percentage), showed an inhibitory effect on the activities of CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4, with IC
50 values of 6.12%, 2.72%, 10.00‒30.00%, 14.31%, 12.96%, 12.26%, and 3.72%, respectively, and had an inhibitory effect on the activities of the transporters MDR1, BCRP, and organic anion transporting polypeptide (OATP)1B1, with IC
50 values of 0.15%, 0.75%, and 2.03%, respectively. This suggested a high risk of drug interactions of SMI when clinically combined with the use of the transporters MDR1 and BCRP substrate
[148]. SMS selectively suppressed intestinal, but not hepatic, nifedipine oxidation (a CYP3A marker reaction) activity in a dose- and time-dependent manner. Three-week SMS treatment decreased the maximal velocity of intestinal nifedipine oxidation by 50%, while the CYP3A protein level remained unchanged; among the SMS component herbs, the decoction of
Ophiopogonis Radix decreased the intestinal nifedipine oxidation activity
[149]. Based on an inhibition kinetic investigation of various UGT isoforms, ophiopogonin D was found to noncompetitively inhibit UGT1A6 (
Ki, 20.6 μmol/L) and competitively inhibit UGT1A8 (40.1 μmol/L); ophiopogonin D’ noncompetitively inhibited UGT1A6 (5.3 μmol/L) and UGT1A10 (9.0 μmol/L); and ruscorectal competitively inhibited UGT1A4 (0.02 μmol/L)
[81]. The ginsenoside Rg
1, ophiopogon D’, and schisandrin A are potential inhibitors of sodium taurocholate co-transporting polypeptide (NTCP) and probably interact with NTCP-modulating clinical drugs. The ginsenoside Re and schisandrin B are potential NTCP substrates, and their NTCP-mediated uptake could be inhibited by other ingredients in SMF
[75]. The ginsenosides Rb
2, Rc, Rg
2, Rg
3, Rd, and Rb
1 are P-gp substrates, and
Schisandra Lignans extract (SLE) was found to significantly enhance the uptake and inhibit the efflux ratio of the ginsenosides Rb
2, Rc, Rg
2, Rg
3, Rd, and Rb
1 in Caco-2 and L-MDR1 cells. Additionally, a rat study showed that a single dose and multiple doses of SLE at 500 mg/kg could significantly increase the AUC
0–∞ of Rb
2, Rc, and Rd without affecting the
t1/2 [150]. The chemical structures of the major circulating SM compounds are shown in
Figure 1, and their potential action target pathways are summarized in
Table 1.