# Anjiang formula inhibits PVN microglial activation and lowers blood pressure by targeting RhoA/ROCK2 pathway: a retrospective clinical and experimental study

## TL;DR

Anjiang Formula lowers blood pressure in elderly patients by targeting the RhoA/ROCK2 pathway in the brain's PVN region, reducing neuroinflammation and oxidative stress.

## Contribution

This study identifies Shinflavanone in Anjiang Formula as a direct ROCK2 inhibitor, linking its antihypertensive effects to central neuroinflammation suppression.

## Key findings

- AJ reduced systolic blood pressure by 10.2 mmHg in elderly patients with hypertension.
- Shinflavanone was identified as a direct ROCK2 ligand with a K_D of 20.0 nM.
- AJ inhibited RhoA/ROCK2 signaling, reduced oxidative stress, and suppressed microglial activation in animal models.

## Abstract

Neuroinflammation in the hypothalamic paraventricular nucleus (PVN) drives sympathetic overactivity in hypertension. The Anjiang Formula (AJ) shows clinical antihypertensive potential; however, the precise molecular targets mediating its central neuroprotective effects remain undefined.

In this translational study, we investigated the clinical efficacy of AJ and tested the hypothesis that it directly inhibits the central RhoA/ROCK2 signaling axis. We integrated a retrospective cohort analysis with mechanistic validation. Clinically, 85 elderly patients with Grade 1 essential hypertension were treated with AJ (n = 43) or lifestyle control (n = 42) for 8 weeks. Target engagement was verified using surface plasmon resonance (SPR), microscale thermophoresis (MST), and cellular thermal shift assays (CETSA). Mechanisms were validated in Spontaneously Hypertensive Rats (SHRs) and Angiotensin II-stimulated microglia.

Clinically, AJ reduced systolic blood pressure (SBP) by a mean difference of 10.2 mmHg compared to controls (p < 0.001), with a 93% responder rate. This was accompanied by improved flow-mediated dilation (+1.3%) and reduced serum IL-6. Biophysical assays identified Shinflavanone as a direct ROCK2 ligand (K
D = 20.0 nM; CETSA ΔT

m
= +5.2 °C). In SHRs, AJ lowered blood pressure and suppressed PVN microglial activation. In vitro, AJ inhibited the RhoA/ROCK2 cascade, downregulated JUN, and upregulated CREB1/NQO1, thereby reducing oxidative stress. These effects were abolished by the ROCK2 agonist lysophosphatidic acid.

AJ provides antihypertensive efficacy in elderly patients. These benefits are mechanistically driven by Shinflavanone-mediated inhibition of ROCK2, which attenuates central neuroinflammation and restores redox homeostasis in the PVN.