About TestoCore Hormonal Wellness

YURI KARUKIN

CLInic director

I founded TestoCore because I know firsthand what it's like to struggle with low hormones. After years of feeling exhausted and being told everything was "normal," I discovered low testosterone was the cause. The right treatment gave me my energy, focus, and drive back—and changed my life.

Today, I help others achieve that same transformation through personalized hormone optimization, medical weight loss, and longevity-focused care.

I don't just recommend these protocols—I live them every day. At 55, I stepped onto a bodybuilding stage and became a champion. I'm committed to practicing what I preach because I believe the best way to guide patients is through both knowledge and personal experience.

My goal is simple: to help every patient feel stronger, healthier, and perform at their best.

STACY KARUKINA

PATIENT COORDINATOR

As Co-Founder of TestoCore, Stacey is dedicated to making every patient feel welcomed, supported, and cared for from their very first interaction. With a background in business and customer service, she oversees the clinic's day-to-day operations while ensuring every patient receives a personalized experience.

Stace believes exceptional care goes beyond treatment—it's about building relationships, listening, and making every patient feel valued. Her compassionate, hands-on approach helps create the welcoming environment that defines the TestoCore experience.

Whether she's coordinating care, improving operations, or simply checking in with patients, Stacey is committed to making every step of the journey as seamless and comfortable as possible.

MARNIE NICKELS

MSN, APRN, FNP-C

Marnie is a compassionate Nurse Practitioner with over 20 years of experience in healthcare. A native Floridian, she proudly serves the South Florida community where she has built both her career and her family. Marnie is passionate about helping patients achieve wellness and vitality through personalized, comprehensive care in anti-aging, wellness, medical weight loss, and hormone optimization. Outside of her practice, she is a proud mother of three and the wife of a dedicated firefighter, drawing inspiration from her family and community every day.

STEVE LIZANO

DNP, FNP-C, APRN

Steve is a doctorate-trained, board-certified Family Nurse Practitioner with over five years of advanced clinical experience providing comprehensive, patient-centered care to individuals from all backgrounds.

He specializes in hormone optimization, testosterone replacement therapy (TRT), erectile dysfunction treatment, and medically supervised weight loss. Steve believes that everyone deserves to feel strong, energized, confident, and in control of their health - regardless or age, gender, or lifestyle.

Through secure, convenient telehealth visits, he develops personalized treatment plans that are evidence-based, results-driven, and tailored to each patients unique goals and physiology. His goal is simple: help vou perform at your highest level

ERIC DIFFENDEFER

NUTRITION AND TRAINING

Coach Eric brings over 18 years of experience in bodybuilding, nutrition, and applied biochemistry, along with a culinary degree from Le Cordon Bleu. He specializes in developing precise nutrition and training strategies that enhance body composition, performance, and overall health through a science-driven, results-focused approach.

With a strong emphasis on hormone optimization, Eric designs customized protocols that align nutrition, training, and recovery with TRT and supplementation plans. His methods are built to maximize efficiency and sustainability-helping clients improve metabolic function, build lean muscle, and achieve measurable, long-term results.

KYLE PIAZZA

PHYSICIAN ASSISTANT

Kyle graduated summa cum laude from Florida Atlantic University in 2019 with Bachelor of Science in Neuroscience and Behavior. He then attended physician assistant school at Keiser University in Fort Lauderdale where he earned a Master of Science in Physician Assistant studies. He has worked in several fields including psychiatry, orthopedic surgery, and emergency medicine, and is certified in Botox and Filler. He also holds a membership to the American Association of Physician Assistants.

Kyle has a passion for helping people. A fitness enthusiast himself, he aims to help people achieve their longterm goals, fitness and other. He also wants to raise awareness of health issues that men face.

Kyle competes in Brazilian Jiujitsu and received his black belt in 2024, He is a member of the international Brazilian Jiujitsu Federation.