Telmisartan and thiorphan combination treatment attenuates fibrosis and apoptosis in preventing diabetic cardiomyopathy

Aims: LCZ696, a first-generation dual angiotensin receptor-neprilysin inhibitor (ARNi), is effective in treating heart failure patients. However, the role of ARNis in treating diabetic cardiomyopathy is poorly understood. This study evaluates the efficacy of a novel combination of telmisartan [angiotensin receptor blocker (ARB)] and thiorphan [neprilysin inhibitor (NEPi)] in ameliorating diabetic cardiomyopathy while, at the same time, exploring the relevant underlying molecular mechanism(s).

Methods and results: Diabetes was induced by administration of streptozotocin (55 mg/kg, i.p.) in male Wistar rats. After 4 weeks, diabetic rats were subjected to either thiorphan (0.1 mg/kg/day, p.o.) or telmisartan (10 mg/kg/day, p.o.) monotherapy, or their combination, for a period of 4 weeks. Metabolic and morphometric alterations, failing ventricular functions, and diminished baroreflex indicated development of diabetic cardiac complications. Apart from morphometric alterations, all pathological consequences were prevented by telmisartan and thiorphan combination therapy. Diabetic rats exhibited significant modulation of the natriuretic peptide system, a key haemodynamic regulator; this was normalized by combination therapy. Histopathological studies showed augmented myocardial fibrosis, demonstrated by increased % PSR-positive area, with combination therapy giving the best improvement in these indices. More importantly, the combination of thiorphan and telmisartan was superior in attenuating inflammatory (NF-κB/MCP-1), profibrotic (TGF-β/Smad7) and apoptotic (PARP/Caspase-3) cascades compared to respective monotherapies when treating rats with diabetic cardiomyopathy. In addition, diabetic heart chromatin was in a state of active transcription, indicated by increased histone acetylation (H2AK5Ac, H2BK5Ac, H3K9Ac, and H4K8Ac) and histone acetyltransferase (PCAF and Ac-CBP) levels. Interestingly, combination treatment was sufficiently potent to normalize these alterations.

Conclusion: The protective effect of novel ARB and NEPi combination against diabetic cardiomyopathy can be attributed to inhibition of inflammatory, profibrotic, and apoptotic cascades. Moreover, reversal of histone acetylation assists its protective effect.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:115

Enthalten in:

Cardiovascular research - 115(2019), 2 vom: 01. Feb., Seite 373-384

Sprache:

Englisch

Beteiligte Personen:

Malek, Vajir [VerfasserIn]
Gaikwad, Anil Bhanudas [VerfasserIn]

Links:

Volltext

Themen:

Angiotensin II Type 1 Receptor Blockers
B79L7B5X3Z
EC 2.3.1.48
EC 3.4.24.11
Histone Acetyltransferases
Histones
Journal Article
Neprilysin
Protease Inhibitors
Research Support, Non-U.S. Gov't
Telmisartan
Thiorphan
U5SYW473RQ

Anmerkungen:

Date Completed 05.03.2020

Date Revised 05.03.2020

published: Print

Citation Status MEDLINE

doi:

10.1093/cvr/cvy226

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM288217454